screws are on the bottom of that CP and it latches inside at the top with luggage style snaps. It is rolled sheet-metal.
It has a hinge so it swings down from the top.
There are several button configurations to be found on that style control panel, and they all show up on eBay from time to time. It is a 2 minute operation to swap the control panels. Wiring the buttons and stick are another matter however...
Check out this one at the bottom of the page:
http://www.mantisamusements.com/vidmisc.htmBy the way, I would love to hear of a place that had BLANK or uncut panels for the old Dynamo cabs.
Once you work with putting controls on metal you will never go back to wood hacks. The install is so much more natural and no bevils or awful looking "mounting plates" required.
The new Dynamos are nice, but they are expensive, and the CP's don't swap with older units without some modification.
On a side note, many believe that these cabs are all after market. That isn't really true. SNK had them make the original cabs for Ikari Warriors for example.