The spin on gauge (spin-lok?) is too big for our spot, you have to use this style:
https://www.vdo-gauges.com/accessories/instrument-mounting/stud-mount-conversion-kit-for-2-1-16-vision-and-cockpit-series-gauges.html
Somebody sells a plastic front panel that snaps in that has spots for gauges, but naturally I can't find it now.
I made mine out of a CD holder I bought from Woody and a sheet of black plastic I got from a display at O'Reilly auto parts.
A friend of mine did his, and I made him a template in Front Panel Express, and it worked out pretty good for him. Unfortunately it is lost as it was on my old laptop...
Maybe a voltmeter? Or if you are going to do some track work, some switches to control your cameras or any other gadgets you may have