[Coco] Opening and cleaning an FD-501 controller.

[William Schaub]

I have an FD-501 controller that has been sitting in a garage for a 
couple of years, upon taking a close look at it it looks like its a bit 
dirty, I would like to open it up and clean it off before trying to use 
it.  I do also have a J&M controller but its still in St. Louis so that 
wont do me much good.  any tips for safely opening the cart and cleaning 
off the crud without damaging the unit would be quite helpful.