Couple of questions for you Don, What type of resin were you using on the body? Polyester, vinyl ester or epoxy? Also is there a specific reason for using matting as opposed to E-glass?

I've done some fiberglass work on wooden boats and use epoxies and E-glass. I've found both to be very easy to work with and not nearly as nasty as polyester resins. Epoxies are also waterproof, polyester resins can allow some water in over time potentially allowing the wood to rot underneath. Probably less of an issue with a car, which will only see occasional splashing as opposed to a boat.

BTW, quick and dirty fairing compound, and less expensive than "tiger hair" or "Mar Glass". Mix fine sawdust, They call it "wood flour" in the boat building hobby, with the resin until it reaches a peanut butter consistency. Probably doesn't have quite the same fiber strength that the chopped strands do in Tiger Hair, but good enough for fairing and filler. Cheap too.