"Lots of work/expense to swap in a 318; if you're only looking for a stock 318 power level, you can get that in a slant 6 with a 2bbl carb, mild cam, and bigger exhaust pipe."


Huh?

Even if you do all that stuff you're still missing about 80hp/100 lb/tq compared to a stock 2barrel 318. About the hardest part of doing a /6 to 318 swap is getting the lopsided lump out of the car without trashing the bulkhead connector, after the 1st time you learn to disconnect it and push it inside the car.

On a 67-72 A body a /6/904 to 318/904 swap shouldn't take more than 1 day, if it does you're doing something wrong.