I stumbled across this thread on m5board.com regarding the use of X5 bushings in E39 arms. Interesting. There's also a reference to an aftermarket part Vines Automotive is selling. The buyer doesn't appear to be too happy, but that may be the doing of the mechanic rather than the part.
http://www.m5board.com/vbulletin/e39...-bushings.html
