I don't have an Easy Star, but here's an idea that might stir up something better.

Looking at pictures, it looks like the motor is friction fit into the pod. You could put a balsa plug in there and mount the motor to the plug (I'd consider gluing a thin piece of ply onto the face of the plug to give something for the screws to hang on to).

This might move the CG back a bit. It would also move where the thrust is being produced. Is it possible to make a shorter plug so that the motor mounts fits a bit inside the pod area? If you cut the shaft and make sure the prop adaptor fits as close to the motor case as possible, you may be able to minimize both of these changes.

Something else: the Easy Star is direct drive, turning a 5" prop. What kind of prop does the outrunner require and will it clear the rear fuse?