Mark, great choice on the truck. I'm a big fan of the little Cummins' engines. The 5.9 6BT only weighs about 300 lbs more than the original engine in your proposed truck. It'd have plenty of power and torque to spare. In the real world it'd be a bit of a challenge to actually do the conversion, although it's been done by members on this board and they may jump in with first hand experiences on the conversion.

Definitely go with Option 1 and the stock frame for a real working truck.

Consider a GMC 302 for the powerplant, it'd be a good option in the real world and again fit the old truck like a glove. Here's a conversation about 302s.

Good Luck,

RonR

Last edited by moparguy; 01/26/2022 2:59 PM.
RonR


1951 3600 with Clark flatbed, T5, 4.10 rear
1970 340 Duster
1990 5.0 V8 Miata (1990 Mustang Gt Drivetrain)
1964 CJ5