30 offset is just too crazy on the W124!
I have 18x8 ET34, and with all fenders rolled, front fender shaved and body cladding cut, it works.
But then again my car is lowered. But if you lower yours, then forget about it, you're gonna rip your 1/4 panel off in a second!
and Mike, thanks for the comments. I suggest you take a look at bekker's (
www.bekkers.com) line of replica wheels. they are the most true to original that I have ever seen, and are relatively cheap!