Thanks to my upgrade to Bridgestone Potenza RE-71R 225/45R17 tires on the stock 17x7 ET40 Racing Hart wheels, I encountered rubbing in the rear on the way home from the tire shop.
- Muteki SR48 12mm x 1.5 steel, open ended, fully threaded lug nuts
- Two cheap 12mm x 1.5 hardened steel nuts for seating the ARP studs
- ARP extended wheel studs (100-7719 and 100-7720, quantity 2 each)
- Various cheap 4x100 54.1mm hub-centric spacers: 5mm, 15mm, 25mm
Spacers are just chunks of aluminum, so as long as they're drilled properly any cheap brand is fine, but upgrading to ARP wheel studs is a requirement. I did all four wheels for consistency, though I only really had to do the rear.
Note that the later NA and all NB Miatas have two different studs, front vs rear, hence two different ARP part numbers.
This much clearance is more than sufficient, given you have no intention of turning the wheel or causing the suspension to become loaded in any way.
After 15mm Spacers
Painter's tape added so fresh wheel rubbing can be quickly noticed.