daily driver on its last leg

Since a daily driver, you might consider if gas goes to $5/gal in a few years. Then you will miss your 4 cyl. I had an 82 Chevy S-10 pickup that got 39 mpg hwy. It was typical era GM junk (mirrors fell off, handles broke), but since the first year of the S-10 and a shortage of GM 4 cyls, they put an Isuzu engine in it. That was the best part of the truck. I would save the 318 for another time.