I got some 15x8 SBP steel wheels from Vintiques a few years ago and never measured the BS when I got them. I finally got to where I needed to check them for my cars build and they were 4 3/16” instead of the 4 1/2”. The 4 1/2” wasn’t going to work anyways but that’s not the point. I called Vintiques and they said it had been too long since I got them so they wouldn’t do anything about it. So lesson learned always measure your wheels I guess. I needed 5 3/8” backspace to center my wheel in the back. I used a 1/2” spring offset kit from Dr. Diff so I gained a 1/4” on each side. I sent the wheels to Weldcraft which is the only place I could find that would do the work. They said 6 weeks turn around and it only took 2 1/2 weeks to get them back. Their work looks good and now I know my wheels will fit perfect. They do all kinds of wheel work so if anyone ever needs anything done they are worth checking out.