FE,
I'm sure you know more than me then! LOL
Promised I'd post my findings. Here they are.
Used thin styrofoam 1/4 thick and placed small ammount of BONDO (polyester) catalized resin onto it. It ate through in less than a minute!
On the possitive side Caswell makes a sealer that will seal polyester resin against gas, or so they claim.
In conversation here, I'm having trouble understanding the difference between epoxy and poyester resin. What is a good local source of epoxy fiberglass resin fitting this application? I've read a few other posts which also agree that a sealer is not required with epoxy. My main issue is that these morons get on the internet and blab about stuff they have no clue. I've read alot of conflicting information regarding resins and the process of application, sanding ect.