http://www.peachparts.com/shopforum/...quaif-lsd.html
Pretty sure the 202 diffs are all open. If you have ESP the brakes act as a sort of electronic diff, but for ASR it just cuts engine power.
The 190e clutch pack LSD is the easiest by far...after that i reckon the W208 CLK55 220 diff with Quaife complete with CLK55 axles and driveshaft(possibly have to change output shaft flange to 4 finger amg style and cut a space above diff like on the w202 C55)