So that means it's going to be a bit difficult for the Tigers also the KV-1 (I was also wondering if there was BB sets for this tank too) to have ball bearings installed in the wheels? I guess the wheels can stick with bushings and have the inner tranny gearboxes using ball bearings then. That would be good enough. I know it may be a bit difficult to modified the holes of the wheels for the tanks to make them just the right size to use BB's. I guess this is why some of Tamiya tanks or I think all of them barely used BB's or not and most of them comes with bushings. But BB's are a nice upgrade.