I just replaced a rear window regulator on my '95 S320 lwb. You need about a 3/16 drill bit to drill of the pop rivet heads (the size is not crucial).. the original regulator uses a plastic slide that both ends of the cable hook into, the plastic breaks (duh) and the cable end pops out and jams the window (usually down) the replacements regulator ($218 canadian) has a metal slide...so someone realised the error of their ways...good luck it took me about an hour and a half to re and re.
Chris