Welp, they're back in the back. They still shift around and go off-balance. I'm finding that the zip ties can't keep them tight enough - the tie just slips back apart. So looks like I'm back to putting a peg down into the center cap. Right now thinking a PVC pipe end as close to the diameter of the opening as possible, then shim it out with electrical tape until it seats tight, and screw it to the center of the cover. And of course, drilling out the lug nuts is increasingly sounding appealing.
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