Your the WINNER! $35 voltage regulator @ a .com for an 04 slk320 instead of $78 for an 04 xfire. Never in my life would I have believed that a M-B part would have a better price than anybody! FYI there are 56 combinations of alt. an voltage regs that will fit a coupe.(All being a Bosch 120amp, 14.4vv.)