For a quick/free check:

Loosen lugs, jack vehicle corner and put it on a stand, friend applies brakes, use jack to support wheel, torque lug bolts to spec, lower vehicle corner, repeat for other three wheels. This way, there is no load on the wheel while you're tightening the bolts. Take it out for a drive. This trick works, but is not a replacement for centering rings. Like others said, they are a good investment.

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Previously owned: '03 4.6iS Dinan Supercharged