im building a 1/12 house of balsa p51 and am powering it with a ap hornet 09 engine. the engine is kinda wierd because of its backside muffler. but im having trouble installing the prop (airscrew 7x4) and the spinner (dubro 1 1/2"). the kit has a ply spinner ring and suggests that i sand the front end of the fuse to leave a 1/32" gap between it and the spinner backplate. but when i try to test fit the prop and spinner, there are only about 2 threads left on the crank shaft for the prop nut. but the prop nut supplied with the ap hornet engine is a combo of a spinner and nut, and thers no room to put it on. do i use a different nut? or am i supposed to make more room on the crankshaft? (there is a thrust plate at the begining of the crankshaft...so i leave it there or take it off?) sorry but im a noob and need lots of help building this kit...i have pictures but dont know how to post...i can email to show u guys...maybe youll understand my pictures better....any help would be great please!!!