Of course it might just need some TLC inside the carb. Then there is that bug-a-boo, Ford and their 'silent' timing chain/gear assembly. Of course the fuel pump may be going away too. And then, there is that fuel filter............some are mounted in-line, others are on the carb inlet and a few were even mounted on the fuel pump

Depending on the particular engine arrangement, some of these '60's vintage 289's had a dual diaphragm vacuum advance/retard - and these are interesting as they can be removed and a single installed but "other things" need to be done as well.