On a 68, without the build sheet, I do not believe there is a way to match VIN to SO number.

The fender tag, radiator support, and trunk should all match.

This thread has good info
https://board.moparts.org/ubbthreads/showflat.php?Cat=0&Number=5877212&Main=5874410

I was looking in the wrong spot for trunk number as well.

The radiator support number shuold be easy to spot.


68 Road Runner
67 Coronet