I asked my old man to prop up a sunshade in the passenger window for me while I was away, but instead he put a blue towel on the passenger seat to protect it from the sun, which I thought would be fine. However after a month or so of it, I noticed that it actually stained my black leather seat a little bit. I used the CG Leather Cleaner, and that got 80-90% of it out, but there is still a spot with a hint of blue tint to it...any other ideas how to get it out?