Best Way to remove white paint from a black bumper

[Ruffrob]

After spending much time and money on my 320,I noticed that someone had grazed their car with mine,and now i have a white streak on my passenger side back bumper. As some of you know,I have a Black 320,and the streak show up like a sore thumb. As always,any and all solutions are greatly appreciated.
If I need to go to a shop,so be it,but the streak is only about 5 inches long,and not even half that in it's width. Holler Back!!!

[sosh]

Some very mild rubbing compound and a little elbow grease should do it.

[Ruffrob]

Thanks,Sosh for your reply...[:)] can you give me an example?......Thanks