Hey all,
I has looking at my 300 gearbox and with the Screws in the motor and the use of a 5.00 prop adapter the one that is used with the APC props I have plenty of clearance. So instead of gluing in the motor and passably having to spend 1.25+shipping for a new gearbox when a crash or burnt motor happens you just spend 5.00 on the adapter and your all set
Here is the adapter
http://www.hobbypeople.net/gallery/648945.asp