It likely is the clutch. Any old Benz's sitting around the shop going to do the work? Usually a good sign.

Be certain there aren't any oil leaks that would allow oil on the new clutch before installing the new one, fix them first,

Replace both the pilot and throwout bearings, friction disc and pressure plate. Resurface the flywheel. Supply new shifter bushings and have them installed. Change the oil in the transmission. Source a throwout bearing arm/fork from a returnable source??? or know where to get one quickly...it's about not tieing up their lift and still replacing it if needed.

If you can, put alignment/reference marks on all of the driveshaft components before disassembly.

Check the driveshaft center support and bearing, and flex discs beforehand and have them if needed. The driveshaft is coming out anyway. If the flex discs are being reused, get new nuts for the old bolts.

Change the oil in the differential.

Hope the clutch master and slave cylinders are good.

Good luck!!!

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