65 swb on 72 lwb 4x4 frame

[idonknow]

Hi all, new to the board but have been reading here for a few months while looking for a project. Not sure which forum i should post in so i took a guess. I did a search of the forums and i can't find something that matches my situation. I have the opportunity to buy a SWB 2x4 65 with a nearly rust free body at the same time that i can buy a 72 LWB 4x4 with a very rusty body. I would like t put the 65 body on the 72 frame, and shorten the frame on the 72 behind the cab to mount the box. My understanding is that the 64-66 and 68-72 frames are very similar, so it should mostly be a bolt on install except for cutting the frame to make the box fit. Does that sound right? Any advice on problems i might encounter?

For background info, where i live a 2x4 pickup isn't very useful for a large part of the year, and this is for my teenage daughters to drive back and forth to school, they love old pickups!

thanks in advance for any advice.