mating 2009 rover wheels and sprockets

[smcmahon]

Good morning. 2656 is trying to repair our Lunacy robot for an upcoming event. We had some issues with the bolts that mate the Rover Wheels and sprockets together.

According to this PDF, the wheels and sprockets both utilize a #10 mounting hole. Needing more of these machine nuts and bolts, I went to The Home Depot last night. I bought a few bags of #10 x 32 2" machine screws (with nuts).

http://usfirst.org/uploadedFiles/200...%20Rev%20B.pdf

I'm currently trying to fit these through the #10 mounting hole in the Rover Wheel. However, it just doesn't fit. It's right on the verge of fitting. If I take a screwdriver and turn, it starts to thread the inside of the hole... and strip the flat head of the screw... (wish I found phillips head instead)

Are these actually #10 holes? Is 10x32 the right size? Should I have to "thread" the holes as I put the machine screws in there?

I have another, very similar machine screw that's slightly smaller. Perhaps #9 (if that exists). It fits 99% great, with about 1% of wiggle room. What did everyone else use?