Kim-1 Computer

I got a chance to take a look at the Kim-1 computer today. It does have the number "0001" silkscreened onto the back of the board near the edge of the board near the connectors. I took a look at one of mine and it had the number 36?? screened at the same point, and the third Kim-1 doesn't appear to have a number screened on (or the light was bad enough I couldn't see it without removing it from the chassis. Anyone else with a Kim-1 have numbers screened on? If so, what are those numbers? I might add this is the MOS Tech board and not the Commodore board. At this point, I don't know if this is a serial number or what, but I'll keep trying to find out. The 0001 machine also has a plastic case for it that looks like it was designed specifically for the Kim-1. I also found a data sheet for the KIMSI S-100 motherboard. Interesting!