RE: Seagull Harmon Rocket
Regarding the two elevator servos, I bought an MPI (Maxx Products?) servo reverser at my LHS for $8.99, works perfectly. Regarding balance, after all is said and done I put all my servos in the standard locations and then bought a Great Planes 2 oz. prop nut weight and the balance came out perfect, no other weights needed. This is with an O.S. 46AX and Slimline muffler, a fairly light power train.
The only real issue/problem I see with this plane is that the landing gear is made of really low grade aluminum and is simply too weak. If you're willing to get creative with making or adapting another set then it's a very straightforward plane to build. On balance I love it... very scale in the way it flies, and challenging enough to fly without being overly difficult, and I'm a fairly low time RC pilot.
RocketRandy