I have a KPC-3 TNC and lost one of the screws a long time ago. I finally lugged it down to the local hardware store and figured out a replacement for the missing screw.
The replacement I got was a 3-48 x 1/4 pan head screw since that was the shortest they had.
You should get a 1/8 version if you can.
You should be aware that there is a side that can take a long screw and one that can only take a short screw.
I put the original short screw on the short side and the replacement “too long” screw on the long side.
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