RE: C'mon CEN
Fuel comes in contact with the carb and the exhaust whenever you run you truck. The parts you mentioned will be fine. The only problem is going to be an oily residue from the fuel.
I am assuming that you are going to use nitro fuel and not diesel or gasoline. Diesel or gasoline might damage the parts mentioned so you shouldn't use either it is also rather dangerous to use gasoline as a cleaner.
rolland