I've used MinWax poly for a long time and never had any problems with it. I have seen posts here that say it is not completely fuel proof, but I've used it to seal fire walls and landing gear plates and never had a fuel proof issue. I'd say that you will be okay since the fuel residue on your fuselage will have little or no nitro in it. But, I always make a test piece before I try anything new with paint. You could make a test section with minimal work and drop raw fuel on it to see the reaction. Let the fuel sit for awhile and then wipe it off to see if it damages the clear. If the raw fuel doesn't hurt anything, your good to go.

Good luck.

Paul