You're right. They are glued on. In most thread on this topic, people have recommend using a dry foam cleaner. Don't get the liner very wet. The foam worked OK for me. I also found that the liner is delicate. If you scrub to hard, it will fuzz or pill up. I had good luck on my wife's filthy Pathfinder, she likes to drive the sunroof and windows open all them time, with Meguair's APC+ diluted to vinyl cleaning strength. I sprayed it on. Just enough to dampen the surface. I wiped, scrubbed gently with a MF. Some times it took a couple of times. Just don't soak it!