That makes both of us bothered by this unanswered question.
As for the PE-245: It was actually the last film chain/slide scanner developed and manufactured by GE, in 1970-71, and - like the live PE-400 color studio camera - carried over to the changeover in 1972-73 to Harris/Gates.
But I also noticed, in the 1958 setup, a PF-8-B slide scanner, a PF-9-C film scanner pickup - and a PE-12-C "color scanner channel." Which sounds more byzantine, frankly, than the PE-24-A/B and all that came after.
It would seem, therefore, that Reitan's reference to GE 3V chains at CBS Television City post-1965 ("CBS Television City used GE Film Chains [3V] during this era") was a typo and that he probably meant 4V. Unless they actually had the 1958 PF-7-A/PF-8-B/PF-9-C/PE-12-C setup. Yet at CBS Broadcast Center in New York, yes, it would be early PE-240. Because of the way the doors were arranged at the bottom part of the PE-240 vs. on the PE-24.
I've also seen GE ads (likewise in
Broadcasting and
Broadcast Engineering) that suggest that ABC's New York studios (and an outpost in Union City, NJ where some film showings originated to get around taxes on film showings in New York) used the PE-24's starting 1964.