Well I guess I am an amateur. I got a Bobcat, stuck a Super Tiger 45 on it with an apc 10X7 pusher prop, took an OS muffler had my brother-in-law take it to the machine shop where he works, they made a brass (round) plate to fit the muffler, I reversed it blowing backwards to push the exhaust away from the plane.

Balanced it at 10.5 " from the L E ( as stated in the manual). Put solid landing gear on the wings and a locked down retract in the nose.

Fueled it up and flew it.

As the old saying goes KISS.