If I were doing a down and dirty swap on this vehicle like this here are the things you need to succeed, assume your donor is in reasonable shape.
1) You will need to swap over the oil pan and pickup tube (and clean out both before the swap to get the coffee grounds out.
2) You will need a 1968-1987 flywheel with the larger hole for the crank register, on the 1975-1987 cars and trucks you need to make sure it's for a high mount starter 3spd or A-833 OD, not the low mount starter bell and 11"clutch...or pull the flywheel and have the center hole honed to the proper size.
3) Check and possibly replace the Timing chain on the donor motor (if good, you might as well take a moment and check the cam/degree it if you have time).
4) Replace the T-stat.
Domestic trucks in the 60's shouldn't have 2 barrels, if it's a later engine from a late 70's truck, the super six setup should reasonably be the same...if it's got EI and the 3874876 distributor, I'd do the EI conversion after swaping engines and getting it running on points to start with.
Truck Engine and car engines aren't too different, some of the early 60's trucks and industrial engines have been seen with shot penned cranks, but I have had a couple of early 60's engines from trucks and torn them down and had no shot peened anything...
Since you have to cut the riser exhaust pipe anyway (for those who are lurking, the 170 needs an extension at the exhaust riser compared to the 198/225, so the exhaust pipe needs a bit more pipe added there to get it to hook up correctly). If you have a few $$ and a student who does a good job and likes to weld...I would go with the 2 1/4" exhaust pipe, new muffler and 2" after that out to the bumper... EI, the 2 barrel, and that pipe should give you a boost in power.
If you had a bit more time on your hands, I would pull the head and clean up the ports, and do a little bowl work just to get a little more out of it with the other mods noted above.
2-cents
