63 gmc suspension

[jnova67]

Im working on a 63 3/4 ton gmc and getting ready to swap in a 1980 c10 front and rear suspension. Im planning to unbolt the crossmembers out of both and ive read I may have to add a couple holes or move a couple which isn't a big deal. The frame on the 80 was cut off after the steering box so im wondering if the 80 steering box will bolt up in the same location as the 63 or is it in a different location? Is there anything that I should be ready for (surprises)? Im also putting a LS in it and was planning on using the 80 frame mounts and motor mounts (I will need an adapter for the LS), I figure if stuff doesn't line up I can drill new holes there too. On the rear I was planning to c-notch and do a flip kit and im hoping that'll get me the ride height im looking for. Im planning a 4-5" drop in front and would like to get it level or slightly higher in the rear so probably a 5-6" drop in the rear. Main concern now is the front suspension and the steering box location since I don't have anything to go off of. thanks

[shortstep60]

You will need to get a power steering plate that bolts to your frame so you can bolt on your 1980 power steering box. You can buy one from captainfab if you need some motor mounts I have a new set of LS motor mounts from cpp I will sale you if you need them good luck.

[siggyfreud]

You'll have to drill two new holes and elongate two existing holes for the crossmember swap. I put an 85 in my 66 GMC. Steering box you'll want the suggested plate. I'm just finishing up a coil over 4 link on my rear. I don't have experience with flip kits, so I'm no help there.

[Captainfab]

If you use the '80 C10 engine mount frame brackets you will need a spacer on top of the '63 frame. I believe it will need to be about 1" thick. The engine mount brackets from a C20 or C30 will fit the early frames better. Let me know if you need a steering box adapter plate.

[jnova67]

thanks for the info and I will probably be needing the adapter plate but I'm having an issue with getting the idler arm bracket to work. the 80 doesn't really line up with anything and the 63 bracket doesn't look like itll work either. does anyone have a pic of the front suspension after the swap? or what steering components do you use?

[Captainfab]

To use the later model steering linkage and idler are, new mounting holes will need to be drilled in the frame. It is best to mount the steering box first and then position the draglink parallel to the frame and the suspension crossmember. then that is where the idler arm needs to be.

[jnova67]

Making a little progress, front crossmember is in and LS is sitting in place. Still using the truck pan and have it sitting probably a little high but the oil pan is about even with the bottom of the crossmember. Does anyone know if the aftermarket motor mounts put the engine down far enough that the truck pan doesn't work? I wouldn't mind fabbing up something to use the stock LS motor mounts if it is going to drop it too far.
Also would like to do a 2 1/2" drop spindle and a 2" drop spring in the front but not sure the wheels I want will fit. smallest size for the front is a 20x9, kinda wish they had a 20x8 but they don't. I will try to stick to about a 28-29" tall tire and around a 245-255 width but not sure this will fit when trying to turn. Gotta do some measuring with back and front space but is anyone running a 20x9 in the front??
As for the rear im still running the leaf springs and trying to drop it enough to get the truck almost level or maybe a little higher in the rear but at most maybe an inch. Not sure if I will have to do a flip kit or if I can get it done with aftermarket shackles. I had to take out 2 1/2" of extra leaf springs from the 3/4 ton springs to try and make it livable going down the road. Looking at a 20x10 for the rear with about a 285-295 width and about 28-29" tall.
If anyone sees any problems with this let me know, thanks for the input fellas!