I've noticed since I've bought the car that the speaker covers (the stock, cloth ones) are a bit dingy. Is there a good, safe way to clean these things?

If I need to take them off of the car, how do I do that?

yah I kinda have the same problem with my TL. Sometimes people will open the door by placing their foot (with their shoes on....argggghhhhh) and push the door open. I think the problem is the cloth over the cloth is tightly on there, and cleaning it will cause it too loosen up, making it almost impossible to put back on and make it look good.