AFAIK rear fog lights are illegal in a lot of places because they can fool people into thinking that a car is coming at them, especially in places where they are not normally being used because they are/were illegal. So that could be something to consider.
I would say that any added lights should probably be LED (without loading resisters) to reduce the risk of burning out the LCM and/or connectors. It would probably be best to convert the filament bulbs on the same circuit to LED and code that way as well.

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1988 325is (purchased new) sold
2004 X5 3.0 2005 X3 2.5
2008 X5 3.0 (new to me)