Doc, it's been months since I doped the fuselage. The damage happened immediately.
I didn't have eight final clear coats though. I had a couple coats of clear over the fiberglass, and then three coats of gold (for coverage), three coats of clear with "fade-proof" ink pigments, and two or three of clear without pigment. These were all Brodak butyrate. The immediate dissolution down to the glass makes me more than hesitant to characterize this clear as even fuel "resistant." This has never happened to any of my planes before. The original P-Force with Brodak "candy" red and a similar coating sequence (no fiberglass though) showed some slight discoloration in a splatter/flow pattern near the outboard tip after flying and being distracted before cleaning, but there was never any damage near or on the fuselage, the pieces of which I still have.
I will certainly extend and/or divert the overflow tube. I'll have a bit greater test next time, when I fly without the muffler to see whether it flies well enough to exchange the boat anchor for a tongue muffler (lost mine!).
SK