HI: What I do every few months is to fill up the kitchen sink with very warm water with joy soap. I bought a bunch of very stiff tooth brushes. Dump the plugs in, let them soak for 20 mins or so then take the tooth brush to them.

Once they are faded, I have several cans of spray paint that I touch them up with.

Most of the time I do not worry about repainting them until they are reallllly bad.

Good Luck.

Giz...