I'm posting this for a friend.....

He has a 2nd gen 4Runner that he just bent the frame on (front lower control arm area) He had planned on doing a SAS before his off-roading accident. He asked me if it would be better to just buy a 1985 4WD truck (if he can find one for a good price) and put his 4Runner body on it. We figured the truck frame would be longer than the 4Runner frame and the body mounts would need to be modified. Has anyone done this? Thanks for the help! (thread says 86 on accident, i meant 85)

 

You'd have to look underneath both of 'em and see. Bring a tape measure.
I do not think there's any difference in the frame rails. They have the same wheelbase (standard cab v 4Runner) so the frame length wouldn't be different. The body mounts are probably different though and would then have to be changed over. For 84-89 this is probably very doable. But don't buy without checking it out with a tape thoroughly first.