Bit-district is considering selling combo sound/volume pots PCB’s for Midway T & U-Unit “daughter boards”. Many Midway games (Mortal Kombat, MK2, NBA Jam, etc) require 3 separate PCBs (and ribbon cables between them) that often get lost or damaged. In short, they’re a mess and most are sold for parts. BD plans to design a single replacement PCB that would attach directly to the main board, so you’ll no longer need to hunt down the expensive/rare audio sub-PCBs and messy ribbon cables.
More info: https://www.arcade-projects.com/forums/index.php?thread/6229-midway-t-unit-and-y-unit-pcb-consolidation-kits/