I would cut the other, unusued arms off your elevator servo. It's a slim chance that it and the rudder servo will bind, but better safe thanb sorry. Otherwise setup looks good.

Center of Gravity on a trainer should be 33% of the chord of the wing. In other words, measure from front to back on teh wing, right next to the fuselage. Divide that by 1/3, and the CG should fall that far back from the leading edge of the wing. It's USUALLY right on the main spar......

Andy