If your question made sense I could answer it a little easier but I will do what I can. I just did a swap with an 85 pickup body, onto an 86 4-runner frame.
The first two pairs of body mounts, from the core support to the fire wall were the same, I had to move the third pair of body mounts back about "5 1/2, to adapt the pickup cab to the 4-runner frame. The body mounts I used were the original third pair of body mounts on the 4-runner frame, I just grinded the welds and welded them back on in the proper place.
To ensure that I had the body in the right place and it was straight, I set the cab on the frame and bolted down the four body mounts that lined up then mesured the distance between the cab and the frame where the rear body mounts were going to go, to make the cab even you need the body to be "5 apart from the frame on each side.
Of course i did the SAS which has nothing to do with location of body mounts. As far as the bed goes I do not have all the factory mounts to mount the bed so I will have to make my own. If you have the 85 frame than you could rob the bed mounts off the frame to assist you in mounting the bed.
Here is the link to my build, I dont think I have a pic or any detail in moving the body mounts but you could take a look.
http://board.marlincrawler.com/index.php?topic=17097.0
Note: your 85 4-runner frame should be the same as the 86, exept the front suspension and arc in frame for the solid axle, which play no roll in the body mounts.
