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Old 07-12-2013, 07:17 PM   #1
nitrosport_5
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A/C Dash Install slice behind dashpad or drill spotwelds?

Ive got my AC dash cut out and ready to install, and am torn between drilling spotwelds on my cab, or slicing the old dash down the seam behind the dash pad. Ive got the replacement dash already out by drilling spot welds, just have not got the courage to start slicing up my cab until i have the idea in my head on what way is the best way to approach it.

SO, if you were in this situation, what would you choose? and why
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Old 07-12-2013, 07:26 PM   #2
elf w/capital T
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Re: A/C Dash Install slice behind dashpad or drill spotwelds?

In MY opinion, i would have better luck with splicing and doing butt welds, just cause tools that i have and dont have. Plus im not the greatest doing that kind of job. But im sure theres MANNNYYY people that have done BOTH ways,
Good luck!!

Have fun and let us know what rout you take.
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Old 07-12-2013, 07:28 PM   #3
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Re: A/C Dash Install slice behind dashpad or drill spotwelds?

Funny how this was just brought up. Last night I tried to remove a dash, drilled the spot welds removed the 6 bolts (2/6 snapped off) and still wouldn't budge. Overall it was a pain in the butt and the dash is still in the truck. May be easy for some but not me I say cut at the dash.
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Old 07-12-2013, 07:50 PM   #4
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Re: A/C Dash Install slice behind dashpad or drill spotwelds?

I replaced my non-AC dash with an unmolested AC dash. I installed a Vintage Air kit and wanted to replace my dash anyway. I painted my replacement dash a head of time before putting it in. I think most guys have to paint it after its installed because they weld it back in. I didn't do this. I didn't drill out all the pinch welds either. I cut the old dash with a cut off wheel and then ground down the area at the welds a little. When I installed the new dash I used panel bond epoxy that body shops use. I used several vice grips to clamp it in place until it dried overnight. This is just as strong, if not stronger than the pinch welds. Plus it allowed me to paint the dash ahead of time, which you couldn't do if you welded it in because of the heat issue. After all the gauges and items were taken out, The removal and install was done in an afternoon. The first picture is of the old dash. It was cut up and had holes like Swiss cheese from the PO. The last two picts are of the new dash installed. I would highly recommend this option. It makes the bottom a little thick because the old dash was cut off and a small strip remained, but I ground it down some and had no problem at all.
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Old 07-12-2013, 07:53 PM   #5
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Re: A/C Dash Install slice behind dashpad or drill spotwelds?

Do yourself a favor and make some templates off your factory A/C dash, transfer them to your original dash and cut them out. Drilling the spotwelds to replace the dash is A LOT of work, and when you put it back in, it has to be straight and the welds need to be smooth for your windshield rubber to fit over it nice, and they are a pain anyway. Cutting at the dash pad is also hard because you have to cut it at the edges on the far right and left sides and it's hard to do, and your left doing body work to get them nice again, Ask me how I know....... I'll NEVER replace a dash again, I'll cut holes.
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Old 07-12-2013, 08:10 PM   #6
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Re: A/C Dash Install slice behind dashpad or drill spotwelds?

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Originally Posted by ls1nova71 View Post
Do yourself a favor and make some templates off your factory A/C dash, transfer them to your original dash and cut them out. Drilling the spotwelds to replace the dash is A LOT of work, and when you put it back in, it has to be straight and the welds need to be smooth for your windshield rubber to fit over it nice, and they are a pain anyway. Cutting at the dash pad is also hard because you have to cut it at the edges on the far right and left sides and it's hard to do, and your left doing body work to get them nice again, Ask me how I know....... I'll NEVER replace a dash again, I'll cut holes.
I would NOT drill the spot welds. Cut the dash with a cut off wheel and remove the 6-end bolts (3 on each end). Done. I had no problem with the windshield rubber installation fitting this set up. I would do it this way again in a heartbeat.
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Old 07-12-2013, 08:14 PM   #7
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Re: A/C Dash Install slice behind dashpad or drill spotwelds?

Personally, Id stay away from drilling the spot welds, Id rather work with fitting the dash than worrying about windshield fitment.
I sliced mine all the way across under the dash pad and welded there. It wasnt all that bad. I think theres a before and after pic in my build thread (I think!!)

If you go that way----it isnt That simple---at each corner you have to cut back towards the windshield and across under the windshield an inch or two--because of the way the ends are braced underneath.
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Old 07-12-2013, 09:24 PM   #8
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Re: A/C Dash Install slice behind dashpad or drill spotwelds?

I cut mine behind the dash pad with a zip disk. It went very smooth. If I had to do it again I would cut it behind the dash pad as I did.
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Old 07-12-2013, 09:35 PM   #9
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Re: A/C Dash Install slice behind dashpad or drill spotwelds?

I've done it both ways and drilling the spot welds is much eaiser.
The only way I would cut behind the dash again is if the truck already had a windshield and I did'nt want to remove it.
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Old 07-12-2013, 09:35 PM   #10
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Re: A/C Dash Install slice behind dashpad or drill spotwelds?

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I cut mine behind the dash pad with a zip disk. It went very smooth. If I had to do it again I would cut it behind the dash pad as I did.
That's a good point and I would have done that on mine, except the PO glued a vinyl cover across the whole top of the dash. It covered right over the vent openings. Because of that I elected to cut the dash below the pinch welds. Your option is a good one, but still requires you to paint after. Thats OK as long as that's where you are with your build. In my case the truck was already painted when I wanted to change out the dash, so I didn't want to have to paint after the dash was installed.
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Old 07-12-2013, 10:15 PM   #11
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Re: A/C Dash Install slice behind dashpad or drill spotwelds?

Do yourself a favor slice it along the slots under the dash pad. I'm a good welder and fabricator. And it works no one will ever see it. And most of all you do not disturb the windshield area. And that can be a problem especially if there happens to be rust along that area, it doesn't weld back very well.

When I did it, I cut the dash along the slots long (let's say furthest from the windshield), and I cut the replacement dash long closest to the windshield.

Then I spent a little time joggling the existing dash metal at the slots.
Then I fitted the replacement dash with some grinding of all those long tabs to fit tight into the joggle. What this does is it makes it to where your lap welding instead of butt welding. And if your using a MIG or TIG welder that is so much nicer to have that little overlap.
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Old 07-13-2013, 09:39 AM   #12
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Re: A/C Dash Install slice behind dashpad or drill spotwelds?

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Originally Posted by nitrosport_5 View Post
Ive got my AC dash cut out and ready to install, and am torn between drilling spotwelds on my cab, or slicing the old dash down the seam behind the dash pad. Ive got the replacement dash already out by drilling spot welds, just have not got the courage to start slicing up my cab until i have the idea in my head on what way is the best way to approach it.

SO, if you were in this situation, what would you choose? and why
I was in your EXACT place a couple of years ago. I had an AC dash cut out by drilling out the spot welds under the windshield on my bench and ready to go in.

Long story short I cut the three holes in my existing non-AC dash and put the AC dash up in the rafters. WAY faster and less painful then all the work to swap a dash.

The only way I'd cut one out and replace it is if it is so full of previous owner holes that it has to be changed out.
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Old 07-13-2013, 10:30 AM   #13
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Cool Re: A/C Dash Install slice behind dashpad or drill spotwelds?

Why would you cut and weld a whole dash in for a few holes in the dash. Just weld the holes up if you can weld the whole dash in why not a few holes.

As far as the AC dash is concerned I would transfer the AC openings into the non AC truck and just hang the AC dash up on the wall for art work. It's so much easier than puttung the whole dash in.
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Old 07-13-2013, 07:18 PM   #14
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Re: A/C Dash Install slice behind dashpad or drill spotwelds?

Andy4639 said it best. Either way you do it there will be cutting or welding involved. So cutting the a/c vent holes in your existing dash requires the least amount of work.
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Old 07-13-2013, 09:08 PM   #15
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Re: A/C Dash Install slice behind dashpad or drill spotwelds?

Found another close up pic of my dash replacement. Cut out old at the bottom, and panel bonded new in place.
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Old 07-13-2013, 10:21 PM   #16
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Re: A/C Dash Install slice behind dashpad or drill spotwelds?

IT's quicker and easier to slice it along the dash pad slots and weld in the new dash with all the perfectly cut holes that uncle GM did.

Example: there is approximately 30" of metal to cut in a straight line behind the dash between the slots. A no brainer. You don't even have to be precise about it. So your total cutting with a muffler cutter is 60" straight inches. With a good compressor maybe fifteen minutes.
And then a little time prepping the two pieces for a butt weld or in my way a lap weld. And lets say worst case an hour welding in along the dash pad slots.

Now the time spent laying out all three holes, and I will add those ball vent holes are not made by a hole saw. Uncle GM stamped those in one simple hit of a die press. Now figure out how long it will take to whittle out those two holes in each end and then the center vent hole which I will sat isn't complicated. And then figure the time it will take to die grind them to a slight resemblance of what it needs to be. I guarantee you'll spend a lot of time getting all three holes cutout.

Trust me the swap out method will be your fastest and cleanest way.
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Old 07-14-2013, 12:44 AM   #17
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Re: A/C Dash Install slice behind dashpad or drill spotwelds?

thanks guys. I tried the cutting of the old dash and screwed up. not as easy to cut the non flat panel with a non round hole.

I think I'm gonna use tlcrz's method and see how it turns out. plus this ac dash is a bit cleaner than my non ac
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Old 07-14-2013, 09:28 AM   #18
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Talking Re: A/C Dash Install slice behind dashpad or drill spotwelds?

It's a very old picture of the non AC dash I did the AC conversion on. The vents will give you some room for mishaps when cutting.Mine are not perfect but once installed u can't see anything wrong with them.

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Get out and drive the truck this summer and have some fun!
It sucks not being able to hear!

LWB trucks rule, if you don't think so measure your SWB!
After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.
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Old 07-14-2013, 11:23 AM   #19
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Re: A/C Dash Install slice behind dashpad or drill spotwelds?

You will not be disappointed in your labor saved and your final results.
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Old 08-06-2013, 03:28 PM   #20
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Re: A/C Dash Install slice behind dashpad or drill spotwelds?

Finally worked up the courage to slice my old dash. It is almost out, just trying to figure out where i want to slice it on the side. Do i want to leave the upper bolt hole in tact on the exhisting cab piece, or do i want to cut above the upper bolt hole? or right through the center of it.

I also left the slots on the cab as long as i could so i have room to remove some material or lap weld.
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Old 08-06-2013, 07:51 PM   #21
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Re: A/C Dash Install slice behind dashpad or drill spotwelds?

Any way you cut it, it shouldn't be a problem. I believe I cut right through the center of the hole, so the bolt covers both pieces. But I believe you could leave the bolt hole on both pieces and overlap them if you think it is best.

The bolt holes were IMO mainly just tooling holes to get the dash located efficiently, so the spotwelding could be performed along the front. Plus there was no way to spotweld it in from the sides.

Either way you go it will be undetectable after your finished from the outside.

Don't sweat it, just take your time and get the welding done. And you'll be finished.


Quote:
Originally Posted by nitrosport_5 View Post
Finally worked up the courage to slice my old dash. It is almost out, just trying to figure out where i want to slice it on the side. Do i want to leave the upper bolt hole in tact on the exhisting cab piece, or do i want to cut above the upper bolt hole? or right through the center of it.

I also left the slots on the cab as long as i could so i have room to remove some material or lap weld.

Last edited by tlcrz1972; 08-08-2013 at 09:21 PM.
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Old 08-06-2013, 07:56 PM   #22
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Re: A/C Dash Install slice behind dashpad or drill spotwelds?

thank you tlzrc. I was going to go through the middle but wanted to see if there was a better option. I really appreciate the reply. it helps having someone that has been there done that! my goal is have the new dash in by the end of the week. will post pictures. going to do a few other things while its out!
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Old 08-06-2013, 08:08 PM   #23
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Re: A/C Dash Install slice behind dashpad or drill spotwelds?

My biggest thought about things to do while the dash is cut out. Is if your into having a nice sounding stereo would be to find some 3" to 3.5" speakers with grills and cut a hole as far outboard on each corner to allow them to fit.
You'll really like the sound they produce bouncing off the window.

I can get you a few finished pictures of mine if your interested.
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Old 08-06-2013, 08:10 PM   #24
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Re: A/C Dash Install slice behind dashpad or drill spotwelds?

Quote:
Originally Posted by tlcrz1972 View Post

I can get you a few finished pictures of mine if your interested.
please do! i love a decent stereo. not into overkill rattle your teeth out, but a nice quality sound with good bass is my thing!
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Old 08-06-2013, 08:43 PM   #25
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Re: A/C Dash Install slice behind dashpad or drill spotwelds?

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Originally Posted by tlcrz1972 View Post
Any way you cut it, it shouldn't be a problem. I believe I cut right through the center of the hole, so the bolt cut both pieces. But I believe you could leave the bolt hole on both pieces and overlap them if you think it is best.

The bolt holes were IMO mainly just tooling holes to get the dash located efficiently, so the spotwelding could be performed along the front. Plus there was no way to spotweld it in from the sides.

Either way you go it will be undetectable after your finished from the outside.

Don't sweat it, just take your time and get the welding done. And you'll be finished.
I cut mine right through the center of the hole and it turned out great. But I do believe you can cut it how ever you wish and it will turn out.
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