From experience throwout bearing usually fails long before the slave cylinder. It's prudent to do all 3 (disk, throwout bearing, slave cyl) at the same time.

The w203 has planty of engineering stupidisms built in (mostly electronic) but I don't think this is one of them. I would love to have a 6spd manual in my c320 wagon and maybe someday I will. The vast majority of the repairs I've done on this car (and there are many) have been much easier than the w124, w201s and w210 I've worked on. MB put a lot more thought into service and repair on the w203 than earlier geberations. The v6 is a packaging masterpiece and everything is easily accessible from the top without too much disassembly.

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CENSORED due to not family friendly words