This is confusing as I'm sure I have seenI also thought of going the cheaper way and just buying mirror covers, but ended buying two used mirrors instead. The reason for this, is because it is not possible to take a + and - cable for connecting the LED warning triangle. The mirrors come from the factory with a "module" inside them where all the wires meet and connect. If however you buy only the "module", then it might be possible. I atleast did not find it, not used and certanly not new from BMW.
Edit: Found an LCI mirror with mirror electrics visible, 99.9% sure I will be able to add the LED wiring to mine.
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