Date registered: May 2005
Vehicle: '07 GL320CDI
Mentioned: 0 Post(s)
Quoted: 1 Post(s)
You've now learned Mercedes rule #1: if you want a feature on your car, have it factory installed.
You can indeed have the HID lights installed. They will cost about $1500 each and labor will probably be about half the parts bill.
There is, BTW, no such thing as an aftermarket solution. Nothing that isn't complete crap, that is.
Mercedes publishes procedures for this conversion, and if you lived in Germany it would be illegal to perform this conversion without also installing headlight self leveling. I'm not sure, but headlamp washing could also be mandatory.
Another example: If you want the roll up screens for your rear passenger door windows, the factory option is about $300. It will cost about $2000 to have these installed after the fact.
A trailer hitch for an ML or GL is $500 factory installed. $2000 installed afterwards at the dealer.