Boat came out yesterday and I did some tests at different ways of removing the VC17. Paint dealer suggested acetone so I did that, it works but as always not without its own issues.

But the reason I write this is that there appears to be something under the VC17 and over the gelcoat and I don't know what it would be. I can see a very small round spot where everything over the gelcoat popped off and the gelcoat appears to be fairly bright white, but when I remove the VC17 there appears to be another layer of a material that is mostly clear but has a yellowish cast to it, makes the gelcoat appear a dirty brownish-yellow. This stuff doesn't seem to come off easily, I have no idea what it is and am wondering if it might be barrier coat that some PO may have applied. Or perhaps some kind of primer? I need to figure this out to ensure it's compatible with what we are putting on for salt water.

Since we're the 4th owners of a 16 year old boat a lot of stuff could have gone on there before we got it. To the best of our knowledge this boat has never been out of the Great Lakes.

Anybody have any thoughts what this might be?