I'm trying to avoid doing a lot of prep work on the surface, but I understand that for some solutions, it is necessary. I'm not familiar with many fiberglass-related products such as epoxy filler. I'll have to look in to that.
I am curious as to what Catalina uses on the interior of their smaller boats. If there is a product out there designed for using on the interior of a cabin, then I think that would be my best option.