Ok well i was wondering how to remove his nasty dirty looking stuff right below the black rubber lining on the bottom of the window where it is flat on the door... lol.. It doesn't wash off obviously... and i sprayed some bug and tar remover, just to see if it would come off.. and it didn't. It was in the shop for a while like 6 months, and i don't know if it could be overspray or what?

 

Try a claybar and some lubricant! Might help but a pic will give others a better shot at finding something to remove the nasty dirty stuff! Oh and yes claybars can remove paint overspray!