[PxTx]

If I was thinking like Smokey, i would use the axles supplied as part of the ballast, then run a set of trick axles on the wheels.

The fact they don't mention the axle slots must be used means you have a lot of control on your car layout and I read it is being okay to drill for a canted wheel set-up.

I would run with 3 wheels touching.

I like mold #10 for wheels, but there are several known to be better.