I’d suggest it depends a lot on how you are building the truck. Is this a stock restoration, a hot rod, or a bagged chassis? If it is going to be a pure stocker driven in parades, changing the front suspension is probably a waste of money. If the truck is going to be modified and driven a lot, the newer suspension would be a nice improvement. Replacement parts are much cheaper and easier to find than the stuff for the torsion bar suspension.
Here’s a thread showing how I did mine should you choose to swap to the newer coil spring/disc brake front end:
http://67-72chevytrucks.com/vboard/s...d.php?t=366828