Since the euphemize bond like crack re-appears every year regardless what's used:
I first dremel/ hog out the crack about 1/8 inch deep. I then use Bondo that has chopped fibers to fill the gouge. I then use regular Bondo for the final finish. Seems like it takes 6 or more fill and sand cycles before I'm satisfied.
I've found that if you wet the bondo area and look at it an angle it greatly enhances imperfections. As in, the type of imperfections that only show up after you think she's good to go and shoot it with primer, then it's........crap. Why didn't I notice that before.
No doubt there's hot rod epoxies that might work a tad better but they all seem to crack. And the hot rod epoxies are REAL hard to sand smooth to obtain the perfect finish.
