I agree with these guys on the dual 1bbls and dual exhausts. Aldo, you might consider finding a later model 235 (58-62) they naturally had substanially more horsepower,had pressurized lube and were 12 volt. Transmission and rear choices depend on a lot of things...what your going to use your truck for, cost, complexity of installation. I've had a lot of luck with Saginaw 4spd, open driveline and 3.42 rear (including axle & brakes) out of a mid 80's full size 4WD Blazer...easy, cheap and a good middle of the road performer.
