RE: World Models Mach II ??????
 

A friend at the field suggested the battery could go up as far as the firewall, under the motor. Could attach with wire ties or velcro. Might hang down a bit but not too much.

Otherwise, though we all hate to add it, some lead in the nose as you have suggested. Could also put on a heavy prop spinner-nut I suppose.

Let us know how she flies!

Best - LeeHop