Cab floor/brace/pillar replacement process

[SixNiner]

Hello to all from a new member! Excited to be starting with my first build project, but was not excited to come across all the rust I have found on my '69 C1500 longbed. Most of the floor has to go, 2 of the 4 outer braces are gone to the point that I couldn't tell what they were, rear cab extensions aren't even there anymore, and the front pillars are shot as well. Outer rockers are junk along with the kick panels and cab corners. AKA YIKES for a new builder!

Unfortunately, I've already taken the passenger door and outer rocker off without bracing first so I need to do that next. But then what? I've been reading a TON and it sounds like a bad idea to cut it all out at once. So do I start at the interior-most part of the floor and work outward? Or just scrap the floor and buy the whole floor with the braces attached from somewhere like LMC truck? If I do that, do I tac weld it in place until I get the pillars/rockers/cab corners mocked up before welding?

Gonna try to start a build thread to keep it all straight but this one may be a bit out of my league. Any info is greatly appreciated and I will certainly KEEP RESEARCHING!

[GASoline71]

In your case it sounds like a whole floor pan and new cab supports would be the way to go.

Or a different cab.

Gary

[SixNiner]

Outside of passenger front support/pillar

[SixNiner]

Driver side rocker. Sorry for the overly large pics, still new at this.

[SixNiner]

And this is supposed to be the rear cab extension but it appears to not be there anymore

[darrellyates]

I agree. A complete floor, which comes with supports and inner rockers, outer rockers, cab corners, and support pillars. Likely inner kick panels as well. I did the same to mine. A better cab is likely less expensive, but depending on what you can find....

Good luck! Keep us posted. Despite all the rust, heartaches, and expense I still love these old trucks!

[SixNiner]

I'm bound and determined to get this thing on the road again. Unfortunately taking the cab off isn't a possibility because of space constraints. If I cut the floor out and replace the cab mounts while it's out, will the cab "settle" because there is nothing holding it up?

[darrellyates]

Yes. It will spread out if you just pop the floor out. I don't think I could get it to line up again... I cross braced mine with 6 pieces of square tubing. Front to back, side to side, and X-braced it.

A complete new floor is a one-piece unit with cab mounts already installed, the front to back bracing, and the inner rocker panels. Much easier, and less expensive labor-wise than trying to repair the floor, and then add the cab mounts. While it's crossed braced and supported, that's the time to do the lower A pillar (door post) repairs, and put in the rear cab corners. All the stuff I bought fit really well, except the cab corners which took a ton of work to make fit correctly.

I tried to post pictures for you, but lack some administrative something to allow me to post. I'll try again, but if it doesn't allow me to post, I'll have to contact the administrator....

[SixNiner]

Darrell awesome information thanks a ton. But dumb question, if I have the bracing in the cab how will I be able to get the new floor in underneath of it without taking the cab off? Rookie question but already gaining confidence.

[darrellyates]

Well, the sad answer from me is... I don't think you can do it without taking the cab off.

in more detail, once mine came off, in addition to cross bracing, there were 4 supports made, basically more tubing welded to the firewall and rear that supported the cab. Once the floor was in,, the cab was re-mounted to the frame, and the corners and outer rockers installed on the frame. The floor was put in off the frame. I don't know of a way to do it on the frame.

The lower door or "A" pillars have the front fenders bolted to them from under the truck, so the fenders have to come loose or in my case, off... And, I had to drill the spot welds off, from the outside of the cab actually, because you can't get to them all from inside the cab. And, then the cab and floor were drilled using alignment pins, and "plug" or spot welded back. Looks very stock, but is a LOT of work.

And, in the final analysis, I don't think you could do it without at least lifting the cab up off the frame. The floor does in fact bolt to the frame after all, and actually installs from underneath. At least that's the way I did mine.

Maybe somebody else knows a trick? I admit to not being the smartest or wisest here. Maybe you could section the floor in? Welds would be visible, but if you did one side at a time maybe you could do it from inside? For what I'm doing, it was just simpler to pull the cab and do it off. I'm running a custom frame anyway, and the only true original part of my truck is likely the firewall and roof at this point.

Just thought you would like to see that the repairs can be done.

As I said earlier, a better cab may be less expensive. I wouldn't have done mine had I known. But, after the media blasting, lots of things appeared that were not visable prior to the media blasting. I thought I had a sound cab, and would up putting in a floor, outer rockers (expected), cab corners, kick panels, and the door hinge pillar bottoms. It's sound now though....

Again, good luck!! Keep us posted.

[SixNiner]

Thinking about leaving the center hump and rear floor brace because they're both in good condition. Then I can do floor pans, rear outer braces and extensions, etc. It will be a patchwork of metal but I've already decided it will never be a show truck. Good first learning experience.

[SixNiner]

Would I help keep the cab from settling by sliding the bed back about a foot, and tac welding angle iron from both frame rails to the back of the cab? Say about 6 inches under the window? Would that help stop the cab from shifting downward?

[SixNiner]

TTT. Anybody have any experience with this? Thanks