Another idea for a kit
 

Back in the late 1970s, a company named Ithaca Audio (later Ithaca Intersystems) developed a near clone of the IMSAI 8080 and called it the DPS-1. It was nearly identical to the IMSAI except for numerous, mostly minor improvements. Among other differences, it had a Z80 CPU, several more front panel functions (but with an identical LED and switch layout), and an active bus termination circuit. A nice feature was that an operator could set both address and data breakpoints from the panel. Oh, and it had a slow step mode just like the Altair 8800b.

Because of its relative late entry to the marketplace the DPS-1 never gained much traction due to its high price and the strong growth of lesser cost machines like the Apple II, Commodore PET, and the Radio Shack TRS-80. The DPS-1 was, if I recall correctly, the last pure S-100 model made; at least it was the last with a traditional front panel.

I'd guess that the number of operating DPS-1 machines is maybe not much more than the number of Kenbak-1 boxes.