I got a deal years ago on an 80,000 mile '71 GTX due to a worn fuel pump push rod. I've seen problems with them for 50 years. Seems like such a simple item. But I'll bet cars and engines have been junked because of them and the inability of the 'mechanics' to discover that they were a problem.

Spare fuel pump push rods and ballast resistors were 2 things that I would always keep lying around.