I’m pretty sure those are just some fiberglass tabs made to keep your tanks in place.  I don’t think the tanks were meant to be permanently fixed to the hull, but just held in place.
As long as the tabs are solid and your tanks don’t move, I think it should be alright.
It could definitely be cleaned up. But back in the 70’s and 80’s, these hulls were being pumped out as fast as possible. Stuff that wasn’t going to be seen didn’t have to look pretty.

By no means am I an expert. Just been around the forums for a long time. If you’re not comfortable with it, it can be redone and isn’t to big of a job. Let’s see what other have to say.


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