Q on E320 Headlight swap...

Hey all, im asking a Q on behalf of my step-dad. He has recently purchased a 2003 E320 in Black (very nice car) and the only thing he is complaining about is the lack of light the headlights are producing...

I just installed some HID lights in my truck and they look BADASS!!!! got them from ebay for 240bux shipped for both heads and fogs and my stepdad really likes them. he took it to the dealer, they said they could do something that would temporarily fix his problem and they told him they made the lights a "euro style" which they said they tilted the lights up slightly, anyways, he asked them how much it would be to switch out the stockers for some HIDS and they quoted him $2500!!!!!!!!!!! WTF!!

they told him the computer is integreated into the entire car and that ANY change would mess it up...

does anyone know if this is true? he has a warrenty on it but he is gonna keep it a while so he doesnt care about it, but we is curious if i was able to buy the hids on ebay, could i install them myself without any computer probelms?

Thanks in advance!

-David