Brad,
That would be a nice solution. I suppose the frame mod would be similar to a c notch in the rear to set it on the pavement - or in your case - put it back where it was. I was thinking of something similar the other day - I was watching some show on the tube doing the rear c-notch, but I will probably try a 2" dropped spindle and 1 - 2" lowered springs first for my 76 - 1/2 ton subframe on the 53Suburban. If I don't like it or run into an interference/alignment problem, I'm thinking I can resale to somebody with a 73-86 truck.
Jim