Hello and welcome aboard. The S10 Chevrolet chassis seems to be a popular chassis swap for the AD. Do a Stovebolt forum/google search and you should come up with some interesting results. Here's a link that somebody posted recently:
Intended as an example of a chassis swap... Now I haven't performed this swap, but I have heard that the S10 frame has a mid-section weld that may be ground out allowing the rear section of the frame to slide in or out of the forward section so that one may adjust the wheelbase.