[Jon A.]

Mystery solved, screw size is 4-40. Kent had a plate that I could thread screws into but 6-32 was the smallest and the mystery screw just pushed in. They have 4-40 screws so I just took one out of the pack and compared it with my screw. I made the initial small investment to bring home a pack and make absolutely sure that they fit before investing in a 100 pack from Fastenal and the same amount of lock washers. I can only buy them in bulk there but it's still cheap. They're still rather obscure and a special order item so I may as well have a bunch on hand. Actually shipping will cost more than the order. The screws used for testing are too long at 1/2", but they're the shortest Kent has.

The parts list in my Space Command service manual is completely useless. It mentions the apparently non-existent 2-32 screw size for the SC600X transmitter that I got my screw from. Quantities seemed to be off the mark as well.