Tire & Trim Restorer on 12 year old Forester =\
I ordered 1oz of Solution Finish to try. I'll let you all know if that works out.
I don't mean to be a Debbie Downer, but I doubt simply applying Solution Finish will solve your problem.. For 1, from what you've described it's smooth non porus plastic trim, so the Solution Finish probably won't be able to soak into it like it would textured trim. 2nd of all you really should fully clean/prep the surface in order for any product to achieve optimal results, and if all you're armed with is Solution Finish or even some APC, it simply won't cut it.
I tried many methods and many products over the past couple of years to restore or at the very least clean this trim and failed everytime...
Super Degreaser wouldn't budge it. Magic Eraser sort of put a dent in it but never fully produced results. Even Mothers Heavy Duty Trim Cleaner did absolutely nothing to clean it..
I tried coating it with TW Endura Trim Coat [which is usually gold] but it turned out a streaky mess [due to it being smooth plastic + oxidized surface] and didn't last anywhere near what it usually does.. I tried Meguiars Ultimate Black Plastic Restorer Aerosol and it looked really bad + was a PITA to try and remove.. Meguiars Ultimate Black Trim Lotion works ok, but doesn't last nearly as long as you'd like + it tends to attract dirt + you're applying it over the oxidation which is never a good thing.
It wasn't until fly07sti gave me a tip about using Mckee's Coating Prep Polish and I tried it to find out it worked 100% to clean and restore that hard non porus trim back to brand new condition.
It won't wipe off without putting up a small fight, but with the proper passion it will fully restore. My advice is start off with the prep polish and a somewhat course terry towel to get the majority of oxidation off, then finish off with terry applicators. Be prepared because there's going to be alot of oxidation coming off.
You'll get a feel for the nuances as you go along and if you're like me you'll get the job done 100% because why not?
My last bit of advice is don't forget to fully clean along the border lip too. And follow with a thorough wipedown with Megs D114 or Mckee's N-914 until all the sticky residue is fully wiped off, then you'll know it's fully clean.
The results even before applying any product will blow your mind.

It's worth the effort. Good luck, hope this helps.
http://www.autogeek.net/coating-prep-polish.html
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