The Liquid Metal Atom steel wheels from Discount Tire Direct came with NO centering rings. DTD was out of this particular size at the time. No rings in the box, no rings pre-installed in the wheels, etc. SO, without the rings, that would leave the bare wheel with a 67.1mm bore which would've been more than enough room to clear the Taurus hub bore of 63.4mm. Offset was fine. The wheels never rubbed when turning or throughout the travel of the suspension. DTD confirmed fitment which was one of the reasons why I bought them. I knew this stuff was going to fit and it DID. I also was a frequent flyer over at wheel-size.com, TireRack and DTD looking, comparing and reading wheel sizes.
The centering rings from the Rage wheels easily stayed on the hub when the wheels were removed. They never snapped into the hub bore of the wheel. They freely go on the hub and freely go into the wheel bore but do not feel loose by any means. They just don't snap in -- I don't know what to say. All I can assume is that the light coat of grease applied to the hub bores kept enough suction to hold the rings.
End of the day the problem is that the effective hub bore was 73mm since the 63.4mm (Taurus Hub size) to 73mm hub centering ring was left on and then a 67.1mm hub bore steel wheel was grossly thrown up on the wheels lugs without any concern to see if the wheel bore would fit over the hub or if the hub would center inside of the wheel bore and then lugnnuts were more than likely ran down to however many hundred lb/ft of pneumatic torque.
FWIW, Crown Vic wheels would fit a taurus, however the offset is too much, Mustang wheels fit Taurus pretty well, Fusion, Mazda 6. Honda wheels would fit too, except most OE Honda wheels have a ball seat and I'm not sure you could find a lugnut with the same thread pitch (Taurus is 1/2-20) in a ball seat.... see what I'm getting at here. I DID do my research and don't willy nilly throw wheels at my cars. I didn't understand the purpose of, nor appreciate the chastising in the previous posts.