Stains on the bumper covers

[Wicked Ace]

Last week I was putting on a lot of miles going to work (and a lot of hours) I got tar up behind the wheel wells and bugs all over the front. I got to wash the car yesterday and got the heavy stuff off. I used Gunk bug and tar remover Solvent based) to get more heavy stuff off. I used 3M Finesse to try to get the stains out but they are stubborn and won't come out. I have a few dark lines behind the wheel wells and yellow stains on the front bumper. The tar and bugs that were on the painted metal came off with washing. Any ideas on how to get them out?

 

[pektel]

Maybe polishing? Like, machine polisher (PC7424 at least), some Menzerna Power finish, and a green Uber polishing pad. Hand polishing ain't gonna do it.

I don't have experience with Gunk stuff. Did you let it dry? Did you specifically follow the manufacturer's instructions?

 

[Wicked Ace]

I don't have experience with Gunk stuff. Did you let it dry? Did you specifically follow the manufacturer's instructions?

Gunk bug and tar remover smells like the old Dupont bug and tar remover( I'm showing my age here) You don't let it dry, Spray on to soak an area for about a half minute then wipe with a gunk treated cloth. It got the surface/heavy stuff off but what ever is in the tar and bug guts has stained the finish. 3m Finesse #83483 and 82876 has done miraculous things with scratches and stains on paint for me in the past so I'm flustered it didn't work. The service manager at the Harley dealer turned me on to it about 10 years ago when I had a problem happen on my gas tank.