Did the rear bumper trim have some scratches on it? I noticed the same problem on a Regal GS in that very same spot when I dressed the trim after cleaning it.
OMG! TWPUG & 845 must be an insane combo!!! The Turtle looks absolutely fabulous, and even can hold its appearance for a surpringly long time (not its slickness though). The Collinite locks it in and the whole package has real endurance... Wow!