The kit will work on the 124 Steve , the instructions won't unfortunately , but the 124 CD has a section on servicing the tilt/sliding roof. I haven't had to do the 124 but it can't be that much harder than the 123.
1985 380SE- 160,000km 'Blistu' - Sold
1988 300CE- Eva,my garage mistress
2007 R350 4matic- The Black Pearl
2011 Ford Ranger-Work truck
1974 25' Trojan Sea Raider- 'Grannyknot'
2002 215 cm Atomic DH skis- Canadian SDH record holder, 175.5km/h- Vars 2010