Heh, heh...like he said.
But seriously, I just have to ask how crud can be building up inside them. Mine are sealed all around including at the bulb. Did you lose the seals that go between the bulb holder and the corners? I know mine is a different model, but the concept should be the same.
As far as cleaning them, I believe that you should
be able to use some soap and water and maybe a soft bottle brush to clean them. However if you do, make sure they a completely dried out before putting back on or condensation could cause some problems for you.
Mike: 1997 SE w/ 183K, aka White Horse
, Gutted Airbox w/K&N, drilled 180* t-stat, tint all around, clear corners w/SilverStars, "PONTIAC" light up tail, PEMs, NGK TR55s