Steve I had to use one short axle spacer, then used a white nylon spacer 1/16 to get the wheel inside the drive side wheel well.
I guess since the spur has a robust collar on it you are not going to see any slop without the spacer. Rules-wise I dont think they prohibit removing the spacers on the spur side.
"... get on your bad motor scooter and ride!"
Sammy with Montrose