26mm was stamped on the wheel hub, but unsure if that is it. They said they don't need it as they are custom wheels. They did get some measurements on 2012 SRT-8 so we'll see. They gurantee a perfect fit.I presume you are upgrading more for looks than performance, in which case I would say go with 21s because I think they will look better albeit at a higher cost. Were you ever able to get the specs on the back spacing?
I think it will be the perfect compromise...don't want 22's, but if I'm paying mucho denero I want a little something lol. 1" can be significant (there's a million jokes in there) on this design as the fingers/spokes will look that much longer. We'll see....:grinbiginvert:Larger wheels are so much a personal taste thing.... For example, the stock 20s look awesome, but when beside the 22s they look tiny (to me the larger wheels look way better but I know many others prefer the smaller wheels with more sidewall on the tires.....).
IMO, If you are going for looks, I am not sure a 1" increase will give you that big of an impact....