Just buy her a set of these...
http://www.bimmian.com/Headlight-Ref...W-E82-1-Series
They work great. Yeah, I would not risk taking apart the headlights on the 135 due to the condensation issue and replacement cost of $2000. The e46 is easier b/c the headlights come apart very easily...had a couple of friends do this.
BTW...if you do buy these dont use their tape. Buy 3M dbl sided tape from Home depot.