Need help picking a motor

I am converting a CRT and was wondering the best motor for my application. I am deciding between a 9XL and a 10XL.(would love to be able to afford a neu) I am going to use a true rc 5s 8000mah pack. I would like to gear it to do about 45. I am using a Monster Max ESC (V1 still working "crosses fingers") so I don't have to worry about amps for the esc. Let me know what you guys think.