If you dont have to have emission inspections, you can remove it, plug the vent line from the tank, and drill out the check valve in the gas cap to make it a vented cap. Check post #10 on this thread and I explain how. http://mmb.maverick.to/showthread.php?t=66757&highlight=vented+gas+cap
I cleaned mine about 4 years ago using soapy water. Good rinsing followed by blowing out good with compressed air then a few days in hot sun so the chances for any rust were gone. Difference? Same as it ever was.