hey, YOU'RE the one who asked what would fit.
ya DIDN'T ask what would fit with work....
ya want power?
none of the above have anything to do with a frame swap.....
how low or high do ya want it?
myself, i have a 58 that i'm gonna clip (assuming somebody else doesn't want it worse than i do) with a 76 seville subframe.
about the only thing that'll give me over stock is pwr steering and IFS.
just for the record,if ya whack off the frt part of a full frame caprice, they fit pretty well also.
use a wagon and get bigger brakes (and a 5"wheel pattern)
also. i can't think of 1 full-size PU that is narrow enough to use and not look goofy.
i guess what i'm saying is, tell us what you have in mind and maybe you'll get some help you can use..