I would kill them! My last car was egged and I managed to find out who it was so one night I went to their house and saw their car so I wrapped their car up in saran wrap (I hope I spelled that right)...the next day me and my friend drove by their house in his car and they were trying to get it off...you should have saw the look on their faces, they were pissed. But hey, what comes around goes around, hopefully you'll find out who did that to ya.
the best way to wrap someones car in saran wrap is wrap each panel in a separate piece. that way when they get one part off, they have to get all the rest off individually too. i work at publix.. saran wrap is easy to get off anything when its wrapped around it. just cut it and pull it off..
oh, a good place for it is in the brakes too... wrap the caliper, rotor, and suspension and they'll smell funky for a few days lol and put some on the oil pan if u can get to that.
i hate it when people do stupid crap to others possessions. esp xr's but anything really.. i got keyed a month ago at a place i go every week where i know almost all the people that go there.. i never start anything and its not an oops..
good luck getting that off.. maybe some 2000 grit wet sand, heavy polish and buff and then claybar and wax will make it look better..