I should write a tutorial the way I did it.  I did it almost the way Oscar did it, except I routed an area for squares of plexi over the joystick area, instead of a sheet of plexi on the entire CP.
As for  real control panels, I have a Mortal Kombat CP I should take a picture of.  It's got 3/4" wood/MDF, and the dust washers are mounted right under a sheet of metal that's on top, and the area underneath has been routed out.  I don't know if it covers the entire top or not, though.