70-80 conversion

[dennhop]

so I've been going back into the posts, and I made it about 6 pages back, but still haven't found all the info I was looking for. Hopefully I didn't miss it somewhere, and about to get crushed for my ignorance!
I'm tossing around the idea of doing either a srw to drw conversion, 1st gen to 1st gen, or converting to a d80 from an 01 or later, with the disc brake rears. I can't seem to find enough info on the D80 swap though.

From what I've read, the D80 is going to be a lot wider than the D70 that's on my truck right now, so I would have to cut off the spring perches and move them. Now, could I keep the 2nd gen perches, or do I need to use 1st gen spring perches?

second, would the rear driveshaft need to be modified to fit the pinion yoke? For that matter, would it have to be lengthened or shortened?
(My truck is a 93 W250, CC longbed)

Is there anything else that I'm missing that would need to be done, that I just don't know about yet? I do know that the shock mounts would have to be redone-would it be better to keep them stock to the 93, or modify them to fit the existing mounts on the D80? Thanks all!

[pulltilbroke]

The perch to perch is the same 43.5" on a D80 as it is on a 1stgen 70, You'll have to shorten your shaft about 2"

[dpuckett]

When I did a D80 conversion on a 92 several years ago, the only real thing I had to change was the driveshaft (-1.5" is what I did) and take a die grinder to the spring plates to fit over the 4" axle tube of the D80.

U-joints are the same.
Brake lines bolt up the same.
Parking brake cables from the D80 will fit into the D70 slot on the frame rail. Seems like I had to move something a couple inches, but I dont remember what now.
Takes a gallon of your favorite oil.
Brakes are bigger, so you'll have to learn how to stop with good brakes again. If giong with discs, you may need to change your proportioning valve- mine had drums from a 99.