Chuck, I had the same problem where the plastic film delaminated leaving the colour and the adhesive behind.
Xylene stripped off all the adhesive and most of the colour.
However, be warned, only use xylene in a reasonably well ventillated location and wear a P2 mask at all times. I didn't for the first session and, while xylene is not especially toxic, I tasted xylene for several days. My shop is half of a double garage with a 12" exhaust fan in the ceiling and I finished the job inside while wearing the P2 mask with the exhaust fan running. I had no further problems.
If you can do the stripping outdoors, all the better, but for me, it was raining.