i understand why you can't put a 1st gen body on a 2nd gen frame, but will the leaf springs from a 2nd gen swap over to a 1st gen? I have a '68 SWB truck that I swapped the whole front cross member out of a '79 model truck and gained 5 lug disk brakes. so why can't I do the same with a 4wd. I used my trusty tape measurer and the rears measure the same on 1st gens and 2nd gens. I can only find a 6" lift for the 1st gen and I need more lift. Can I use 8" 2nd gen leaf springs in the rear and the 6" 1st gen leaf springs with a 1 1/2" shackle to gain the amout I need, as I have measured a slight difference in the front leaf springs between 1st and 2nd gens. It seems to me that the frames are the same between 1st and 2nd gen otherwise I wouldn't have been able to swap the '79 cross member and all over to the '68, it was bolt in swap, 2 holes to drill. I looked at catalogs and I see differences in how the frame is made, but it does not measure the same up front, could be the arch of the leaf spring throwing me off. the rear is the same according to the tape measurer. Also the talk about using 52" leaf springs up front providing double the lift, hence 2" lift = 4" of lift. How are you accomplishing this? I don't see how you bow the 52" leaf spring to fit the front. Can I just swap axles from 2nd gen into 1st gen if leaf springs and all won't swap over? I've read all the threads and have seen people ask this question but have yet to see a solid answer. I want to swap my leaf springs and axles out of my '80 model k5 that has been converted to 1 ton and lifted into my newly acquired '69 k5, is this possible or do I have to buy a new lift and just swap axles or is that even possible, my tape says the axels will swap i just hope i can swap springs and all. i have a burnt out '85 truck and plan on making the '80 a 2wd after i get all of my 1 ton and lift swapped so i can run my 39.5's on 69 k5.. Thanks for any and all replies in advance , I look forward to your experties and working through this problem Thank you R. Ray.