Doug:
I emailed a vendor recently asking about a Happs 4-way and this was his reply:
"I stopped buying the 4 way pac stick from Happs because it's only made for thin metal control panels. It required that you rout away over 1/2" of your 3/4" control panel in order for the handle to stick up far enough for pratical use. I now stock the Betson version of the stick. It's identical but it has a longer handle which means you install like any other standard joystick."
I've not yet installed the Betson he sent me, but it looks good.