How much do you think a 72 coronet with a 318 could tow?

A 318 in good shape will tow anything the car is safe towing, it's just that you might "spend a little time" getting up to speed.

Years ago, when I was broke, to get the car "going" I bought a "fifty dollar 318" and put it into my '70 B body. Turned out to be a 273!!!! I towed a few things with that, including a junker Poncho full size wagon that was part of a "deal." (You can have THIS but you have to take THAT)