will a 72 front end fit on my 74?

If you do the entire front sheet metal than I think so, but not just parts. I'm going through the mistake of buying '72 Valiant hood, grille, vallance, bumper and trim only to find that the '75 "big bumper cars" have longer fenders! (I was trying to find out if the inner fenders were the same, but I doubt it.

This scares me because I plan on doing this!