Thanks for the feedback/advice. I wiggled a few of the wires with pliers while cleaning around under there today and, yup, the rubber was crumbling. So I’ll swap out most of it and see how it goes!
Steve, thanks for the information on fire hazard protection. I don’t know what I plan to do for an antenna yet– I’m moving in such small baby steps that even turning it on seems worlds away. Thanks for the warning about the battery cable wiring. I’m hoping I’ll have a sure idea of which is which by the time I’m done swapping things out. If not, I’ll definitely ask before hooking it up. I don’t have the RCC service data but I think I got the Marconi ones from radiomuseum.org. I have three pages of schematic for it. However, I don’t know if that’s complete.
Thanks again for the help. It’ll take me a while to get through this but I’ll post back as I hit roadblocks.
EDIT: I just noticed that in my original post I said it was a Marconi 148…… it’s a 147. Not that it makes a difference to any of the above.