You don't have to mod anything to remove the diff riser with the Grid mount.

Cool. Everything's done now apart from wiring the ESC to the motor and then fitting the motor/mount. Think i'm gonna end up waiting again as the m3/m4 10/12mm screws i ordered ain't even shipped yet. Might just fit the std mount for now so i can at least give it a spin. Away with work for 2 weeks on Monday so this weekends the last chance i'll have for a while..