I would sooner do a radio reset before I would clean the pot. Unless you opened it up and there was just mounds of dirt and dust in there, then yeah... spray it out. But even then... I wouldn't drown the pot in cleaner. If you do spray it, try to use something like RC electric motor spray... something that dries without residue.
KT19 reset post...
http://mini-zracer.com/forums/showthread.php?t=39628
I used to obsess about glitch in the AM days... ever since 2.4, I haven't really dealt with pots much at all!
And as far as getting that assembly out of an 03, I'm pretty sure it slides out the bottom of the chassis. I know I had to take off the top and bottom to get mine out.