I finished my mod to my Atari 50th cab.
Basically put a PC with HyperSpin in there and added an Ultimarc MiniGrip stick.
This way I can play pretty much play any game with trackball, spinner, two joysticks with fire, including those like Mad Planets, Tron and Discos of Tron which need a joystick with a fire button and a spinner.
Unfortunately the trackball and spinner on Atari 50 don't work with the Thunderstick 12 in 1 board, so I had to swap these out for a TurboTwist and a Thunderstick trackball. It was a shame as the stock trackball on the Atari 50 was really good.
I initially planned to upgrade the monitor, but once you apply the MAME HLSL to the games, the stock monitor really pops and I think its about the right size for this cab.
Overall it was a bit of a fiddle, but I'm happy with the end result.