I tried to put 19" XLR-V rims on my car and determined it can't be done. They require a wheel adapter to go from the 5x115mm bolt pattern to the 5x4.75" pattern of the wheels. There is no possible way to make an adapter thin enough to get the wheels to fit. Even if it was possible, you would have to run super short studs to keep them from sticking out beyond the adapters. However, the wheels have a lot of offset so even redrilling them would require some sort of spacer, not sure how this other person accomplished this.
Cardio-Doc is king of Cadillac wheels on eBay. I bought my XLR wheels from him. As TOMM stated, the 18" STS and XLR wheels will only work with much effort. I have the XLR wheels on my wife's CTS. Had to have them "drilled and inserted" to correct the bolt pattern, change the factory wheels studs to longer studs, and use wheel spacers. Only needed on the front, but chose to use on all fours. The 18" STS wheels advertised on eBay are pretty, but I bet they're a pain to clean and keep clean. I personally like the seven spoke, 18" XLR wheels for their "flat" appearance and they're probably the easiest wheels I've had to clean. I would personally prefer at least a 19" or 20" wheel and a lower profile tire than the 235x45x18 currently used. Can't say I've seen any aftermarket wheel that I like. I would pay a premium for a look-a-like 20" XLR wheels that fit without modifications.
