Tom, So do you not thin the 2 hr epoxy? On my last engine compartment fuel proofing I tried your suggestion (made on another thread a short while back) to heat the epoxy with a heat gun but saw only a marginal improvement in finished surface smoothness. I didn't understand that I was supposed to heat the compartment before I put the epoxy on, I just heated it after I brushed it on. I also was using 30 min. epoxy thinned with 90% alcohol. I will try it again on my next build, whenever that is, so should I seek out 2 hour epoxy and not thin it? Do you use the heat gun on the surface before and on the applied epoxy after? Thanks for your help, Larry