Am in the middle of your saga now with my 99e300td. After wringing the nut loose on a GP I decided that I'd just let the dealer fix it. Then I found out their worst case price. $1000 if I'm lucky, another $2400+ if I'm not. Gievn that price, it seems only reasonable to give it a shot.

The plan is to put loosening oil on the GPs everyday twice a day for a full week and then try and loosen them. Since I wrung the "nut" loose, drilling should be relatively (famous last words) safe since I only need 1/2 inch for an easy out to get a grip and I'm up near the head of the GP (as opposed to way down inside the head). I won't try drilling the broken one out until all the others come out fairly easily (after continuous bathing in oil) If two weeks goes by and nothing budges, then I figure fate will have decided my course of action and I'll button it all back up and drive it to the dealer and cross my fingers...

One thing I seemed to discover in my quest for information on this problem - the previous GPs (in years gone by) were much better design - short, squat, and fat - no breaking problems there. Wonder what the engineers were thinking on these...

Andy