For the record, I play my Robotron cabinet on a weekly basis. Otherwise, the skillz get rusty.
It's literally the first thing I play whenever the machine is booted up. No better way to burn off some stress.

Thanks again RandyT... do you have the depth measurement? i.e. from the top surface of the joystick base to the bottom point of the joystick base. This is the only other measurement I need. Cheers.
If you are looking for lower clearances, this changes with the height configuration of the shaft. The restrictors also add just shy of 1/32" to the overall thickness, if one is used. So the recommended below panel clearance requirements are:
Long Configuration: 2.1"
Short Configuration: 2.75"
What's a new centering grommet run?
Replacement grommets will be available to Dominux8 owners for $7.95 each. I don't expect to sell many, though. The ones you typically see in bad shape today were beaten mercilessly for a number of years, dry rotted in storage, had who-knows-what spilled into them, etc... I.e. things which private owners usually wouldn't subject them to.
Also, what shaft length would you need for Robo stick height on a metal panel?
I tried very hard to mimic the length of the two WICO models with the height configuration options. The short configuration is pretty much spot on to the WICO 3.5" shaft model, but the long configuration is about 1/16" longer than the WICO 4" shaft model. The long configuration is a compromise between accurate 4" WICO emulation on metal panels, and accurate 3.5" WICO emulation on wood panels.
The action, however, is significantly different. It will be like using the 4" WICO with the optical upgrade, coupled with a little less resistance. Silky smooth.

One of the interesting things about the design is that the length can basically be tuned within that range through the use of different spacers. I may look into offering a "tweakers" pack of spacers if there turns out to be interest in such a thing.