Additional information, right out of my article; "To increase the amount of confusion regarding 15x7 A-body wheels another variety of wheel was offered. These wheels were produced some time after 1972 and are identical to the Chrome wheels. The only difference is that they were painted, not chromed, and had trim rings. Codes for these are located at the valve stem and have application codes of “WZ”." I would have to check my notes, but these are probably the wheels that came on the pace cars. Duane
