Residue from static cling? Claybar time?

[mac72]

Greetings!

I've got static cling bonnet/boot stripes from Finish Line (cooperaccessories.com) and I've always been careful about their application and storage. The car's always clean and quick-detailed before the stripes go on, and the stripes themselves are kept clean and rinsed well in lots of clear water. Over the spring/summer, I had been keeping them on for a week and then off for a month or so.

In July, I started to notice a difference in the way water beaded up on the bonnet, and when washing the car, I could tell where the stripes had been. I worked on the areas with a wool mitt and lots of clear water, and thought the issue was resolved. Now, however, I've noticed there's almost a residue where the stripes were. The last time I washed/waxed, I thought it went away, but in the sunlight at the right angle, I can clearly see where the stripes were (note that I can only tell on the bonnet, not the boot).

Should I get a claybar and see if the bonnet's blemishes clear up? Or should I use some Scratch-X or some mild polish to rub out the marks? Anyone experienced this before? Thanks in advance for any tips!