i have a first gen bed on my second gen truck if that matters......
for your application, the first gen beds had a removeable front mount that went to the frame, the 2nd gen has a mount on the frame that goes to the bed, and rests on it there.....
they are a little different, when i did mine, i jsut left that mount off, it hasnt shown any adverse effects, also, my bed is bobbed, so i am also not running the rear most mounts, because they were removed, i have 4 of the 8 bolts holding my bed on, and i have loaded it down several times, with no ill effects, the body edges dont stick out further, the lines are off, but are pretty close, if putting the later bed on the earleir pickup though, you will need to drop the body of the pickup or raise the cab to get the lines to match
hope this helps
