Yo Mark - Glad to see the Roach has a new home, hope you have her up and flying again soon! FWIW, I had to add about 5 oz. of lead in the rear of the fuse to get the CG in the correct location when full of fuel (and a P120 bolted on back), so make sure you test-assemble everything and check the CG before permanently mounting your glo engine - you may want to space it as far forward as possible and move the batteries into the nose. FWIW, the CG is marked by the small black (tape) arrows on the wing.

Barry