Mercedes RWD. On the case just above the pan numbers are stamped. They have 722 then three digits. 4 speed start with 3 or 4 . 5 speed start with 5 and then the electronically controlled 5 speed with 6 Also serial no. Its not on a plate
mags
August 2010
have a look on gearbox for its model number, should be on a small metal plate, if the same on each box then should be o.k. or see if haynes do manuals for these cars as that will also tell you if they will fit. Good Luck