If you need to replace the motor think about how you want to use the truck as you decide which motor.
A 292 might be a good choice, especially if you are going to haul loads around town. If you are going to show it and just run it around unloaded, a 283 would have been a factory option, and one I'd enjoy in a truck like that one today.
Or do what I've done. I dropped a 454 into my '72 over the weekend.... Okay, I confess I dropped it into the bed, but hey, a big block is always fun to drive.
