W126 Wheels
 

Can someone tell me how many versions of the factory 15 x 7 alloy wheels were made. I am trying to get a set of original wheels for our 1986 300SDL. I have found a couple of ads for wheels that LOOK the same but have different offsets and widths. The original spare from my car is 7Jx15H2 ET25.
I have found 6 1/2 x 15 M2 which I bought before realizing the various version. Can anyone tell me what these wheels fit ? I also found a set of 7J x15 ET47 or ET49 ? Is there such a thing as an application chart that explains the different numbering ?