I've written this here before, but here again what I've found to be the best, is using some GUMOUT on a folded paper towel, and rubbing, in circular motions, the tar or bug spot. After easily taking off the junk, I then use some Dupont #7 polish, and then a final coat of SIMONIZE,(The old fashioned stuff in the the yellow can). I haven't seen anything work as well as these three products in 30 years of car care. Good luck.