Just swap chassis's, that's what I did.
I have a 49 1.5 ton cab and hood with 49 2 or 2.5 ton fenders, on an 89 1 ton 4x4 chassis with a 454/t400/np205 dana 60 front 14 bolt rear.
I just drove it from San Francisco to Flint Michigan in 5 days.
Everyone LOVES this truck.
49 gmc
49gmc