Thanks for the advice, Fire Escape. Got it on with the spacer on the outside as you suggested. Worked perfectly.
Of course I have to take the cover off again as I forgot to use LocTite and to bend the washer over the nut. Got too excited to ride it and jumped ahead of the plan.
Ah, well. At least I know it'll work. Think I'll like it even though I didn't get to run it up to speed. Pulls away from a stop very nicely.