So BatteredBenz, is it as "simple" as changing out the existing ignition switch?

Like this ?:
Pelican Mercedes-Benz Tech Article - Replacing your Ignition Switch and Lock on your Mercedes Benz - 190E, W124, W126, W201, W123

Good idea, I will try this before the wiring harness.

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1991 300E 124.030 103.983KE 722358 03 412178
207K

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