...you got two hatches you can use later. If the epoxy won't stick well, then you are probably setting yourself up for grief later on. Can you not sand into the spider cracks a little and then use the gel coat? I have never used the stuff before so I don't really know for sure. That said, once Linda (significant other) discovers that little patch of gel coat I accidently removed while scrubbing the bath tub with a too-abrasive scrub pad, I am absolutely positive my gel coat technique will dramatically improve in remarkable time.

Robert (Ai)N(t fixing nothing till I'm caught) Pruden