If, on a scan or looking at a wiring diagram, I come up with a part number, how do i translate that into a Mercedes part number? For example, relay K75 on my CDI, how, without actually looking at the part, can I find the part number?

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14 E250 Bluetec 4Matic "Sinclair", Palladium Silver on Black, 157k miles
06 E320 CDI "Rutherford", Black on Tan, 175k mi, Stage 1 tune, tuned TCU
91 300D "Otis", Smoke Silver on Tan, 144k mi, wastegate conversion, ALDA delete

19 Honda CR-V EX 70k mi
Fourteen other MB's owned and sold
1961 Very Tolerant Wife