I've thought up the sceme for my MT P-51 and would like to paint the tail section aft of the canopy. Besides roughing up the monokote for the paint to take, do I need to do anything else?

Which paint should I use? Lustercoat? Krylon? Automotive?

Will I need to fuel proof?

Thanks!

Just rub the surface to be painted with steel wool #00, just enough to dull the surface, clean the surface well, as steel wool leaves like an oily residue behind. You can use any type of paint, just make sure that it is fuelproof (Lusterkote, Rustoleum, not the silver color, Ace Hardwares have a very good paint in spray cans, it is an epoxy type, their own brand name, I couldn't believe the finish obtained with this paint, and it is fuelproof, of course automotive too).
Just don't spray too heavy a coat towards the tail, or you could end up tail heavy.

Kevlar,

The wool will do the trick just fine and is mandatory if you want the paint to stick. Lustercote works great. Just keep the coats light as this stuff tends to run easily, especially on a surface that is not porous.