Niles, you might want to check out this thread here on the forums, set up specifically for electrical manuals and diagrams:
https://ogrforum.com/t...rials-andamp-manuals
I posted the wiring diagrams for the semaphores on that thread some time ago, they are there for you to check out.
As for the "internal" wiring diagrams, those are probably Lionel proprietary and not published: the same is no doubt true of the MTH reproductions. The internal wiring of the vintage Lionel 82 will be very different from the new MTH reproductions, the new ones use printed circuit boards.