Early Barracuda body cracks under rear window

I never knew it was a thing on the 64-66 Barracudas until I saw this thread. I went out and looked and sure enough, mine was cracked just like the one in @Bob Jasinski pic he posted. If you dug all the old out, welded it solid, sand blasted it, epoxy primed it and then did the initial fill with either All Metal filler or Tiger hair, then finish worked it with Rage Gold it would probably be fine.