hi Telamon:

Actually I got word from someone who said that the '75 was
considered a work in progress that never progressed.

That's an understatement if I ever heard one!

Welcome to the real world. Engineers will play with a design until they
are happy with it but management runs the show. As soon as the pointy
haired boss thinks that the design has met its goals the effort ends.

sounds like the voice of experience.

regards,
phil