I didn't have time to read all these responses but here is mine.
I have only bought one item that was difficult to install on my 3600, that was the rear sway bar. I don't believe anyone makes that product. I was able, using a bit of engineering, manage to fit it in. The point is, you can make it all work. The path I took may be different to what you have planned. I installed a new IFS from Heidts,
www.heidts.com, a 700-R4 automatic transmission,
www.phoenixtrans.com and a 1980 Camaro rear-end. With all that I was able to have 5 lug wheels, 4 wheel disc brakes and a stable ride, all of which is needed around here to stay alive on the road.
Good luck, keep checking here for information. It may be worthless but it's free.
