Guys,
Since many complained of too much up/down in the main gear previously, I tightened up the tolerance on the auto hub assembly for the TT system. With that said, some with rotate perfectly, some will be a bit tight. If yours is tight, simply sand one of the delrin shims down a bit and it will rotate freely.
I do not recommend slotting any holes as the mount distance is based on a mathematical equation for proper spur gear mount distance. Any deviation from the may create problems.
Thanks,
Matt