The mount looks really at home in your RC8Be Gregg!

As for the confusion on the mounting holes for the motor plate. The Neu/Castle motors are like all other motors with M3 holes at 25mm mounting centers spaced 90 deg circular pattern, which is four holes for the motor.

The Tekin is slightly different where the mounting holes are at a 25mm mounting centers but spaced 60 deg circular pattern allowing for 6 holes. The Tekin has four of the six holes M3 and two with M4.

So essentially, any motor can be used.

The ball bearing is a M5x13mm. 1/8 motor for cars application have 5mm shafts. If you decide to put a special motor in with either a 4mm or 6mm shaft, just change out the bearing to a M4x13mm or M6x 13mm.

If you don't like the ball bearing, you can also take it out.

The other thing we highly recommend is to use more than two mounting screws if you are going to racing on a bumpy and jumpy track. With three or more screws, you have added insurance if one comes loose.