If you can find a plate that will cover the hole, I would tape it on, then start with some release agent, resin-soaked glass cloth, and build up from the back to 1/4″ to 1/2″ thick. The plate will give you a good flat surface. You can then pop it off (if you used release agent) and have it finished however you want, or you can leave the plate on, cut/drill holes as necessary, and go from there. If you want, you can go to a local hobby store, buy some K&B polyester resin + catalyst, and some SIG fiberglass cloth and do this without breaking the bank. The polyester resin will be more than strong enough for this, as will the glass cloth (I have used this to build wing skins on a ducted fan jet that almost hit 200mph in the air). Not as blister-resistant as vinyl, but this is not exactly a blister hot-spot since it is not going to be constantly wet.2008 Pantera Classic2014 Mercury Pro XS 200
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