[mongocanfly]

Thing is your truck has the large front hood/fender setup,,(longer/wider)
a small truck frame will be really narrow under there..and I know it's been done..(lower50s)
if your really wanting a frame swap, then look towards a more fullsize truck donor option
Or just keep your orig frame and fab off that..
Trailblazer ss have been used under several trucks on here
If you want LS power, I would look for a frame/engine/trans from a LS powered truck,