I've seen tons of threads about 30 bodies on 32 frames, but what about the other way? Can I put a 32 truck cab on a 1930 frame? would I need to do anything to make the hood match up?
I see no reason you can't, you can make anything fit. All depends on your fab skills. I would start at the front and fit back.
Sure... easy peasy... make new cab/frame wood blocks to fit where the model A frame is, drill new mount holes in the body and/or the frame as needed. Hood fit? What hood? This will be a hot rod. (seriously, if you want to use a 1932 hood with a 1932 or 1930-31 radiator shell the radiator will have to be shimmed up about 1-1/2" which is amazingly the kickup of a stock 1932 frame. Or channel the cab so the hood fits. Any bed you run is going to have to be short because you are losing 2-1/2" wheelbase and some cab length. So why not consider moving the cab back so you have motor clearance AND leg room (maybe even a 1933-34 pickup firewall for 2" more leg room). No hood or custom length. If you even think fenders and running boards they will have to be 1928-29 or 1930-31, 1932's match to the 1932 frame and nothing else. Good luck, have fun.