OK folks, slow down and don't get your hopes too high.
I have been at Zenith since 1975 and I'm still here at the reorganized Z/LGE. However, I worked in the advanced development department (now R&D), so I can talk theory about the old sets, but have little knowledge of what was in actual designs. My initial work at Z was analog integrated circuit design for chroma demods. The guy next to me worked on the color oscillator section, and together we came up with a reference design for a one-chip color section. Then product development took the result and adapted it to actual product design.
Before Zenith, I worked at Motorola, starting in B&W TV, then for a while on a video player (EVR, developed by CBS labs and the famous Peter Goldmark)that never made it in the market, and then in R&D on analog IC design.
These days, I'm into "technopolitics", representing the company in standards-setting bodies like ATSC and ITU, pushing adoption of digital TV technology.
So - don't expect much from me in terms of "what was in chassis number xxxx" - I'd have to find a source just like anyone else.
old_tv_nut