Nuclear Data was a Chicago company that built various bits of instrumentation for the nuclear industry. I have heard they were the company whose computers were at Three Mile Island, but have no documentation on that. The ND-812 front panel is light/dark green as well. I have one in poor condition. The CPU is wire wrapped. There are PCBs for the core memory system. Bunker-Ramo used them in a point of sale system for supermarkets, mostly in the Chicago area. Parts for them would show up at hamfests in the mid-late 70's there, which was the first time I saw one.