Some background information on the CSL wheel arches:
The wheel arches were originaly designed to allow the mounting of the Alpina 7x14 rims/XWX tyres combination onto the CSL. Those arches were made of polished stainless steel with a weight of 520 grams for the front and 509 grams for the rear (according to the books). For rigidity, the arches had a "squared" leading edge as shown in the pictures above. As Motorsport in Oct.73 took over the management of the performance parts, the wheel arches were attributed the same stickers as for example the wing, spoilers and so on (black sticker on the inner side with the last 7 digits of the part number). As some of those arches had run NLA, BMW had a new batch of those made (about 2 to 3 years ago) which look identical to the originals. It is not known to me how well they fit. Also, There are at least 3 type of copies that exist on the market, in chromed brass or stainless steel.
Gerrit