Let me get finished with this project first... While I tested it on the bench; it hasn't yet be tested in the full machine.
I'd like to know for sure it's ready to go before going that route. Also; keep in mind I only had 10bare PCBs made... so we'd have to get more manufactured before I could build a set.

One thing about the design did concern me... I had driven the switches with 12VDC and saw 9VDC at the pins of the Row/Column when the sensor isn't sensing. This concerns me given it's a 5V MPU. Luckily; My GI is DC ~8V.... so I'm going to drive the Prox Sensors w/ 8VDC... to get ~5V max at the row column pins with inactive.