I do remember your comment about this topic Bull.
The spacers are hub centric, this is a absolute MUST for any spacer and any vehicle.
As for the thickness of the spacer the answer is not so simple. The minimum thickness of the spacer will depend on how much negative camber is dialed in at the strut / knuckle bolt adjustment. The more negative camber you adjust in thus moving the top of the wheel / tire closer to the strut the thicker minimum thickness spacer you will need. The less negative camber you have adjusted in the further the top of the wheel / tire is from the strut and a thinner spacer can be used. A drawback to a sub 25mm spacer is that the OEM studs ( or at least one of them ) must be trimmed to fit inside the wheel mounting recesses or replaced with longer studs to go though both the spacer and the wheel, like JTRAX is using on his aftermarket wheels. For my application a 25mm is the absolute minimum thickness as I am maxed out on the negative camber adjustment at the strut / knuckle bolt. As you can see in the pics the clearance has not changed, top is 19x11 no spacer, bottom is 19x11.5 with 25mm spacer.
