Re tube extenders, here's a photo from when I restored my Predicta. One is shown with a tube plugged into the chassis. The others are just strewn around to show different types. I got a whole sackful at a swap meet years ago.
They do come in handy. Before I knew there was such a thing, I hand-built one to test voltages in the RF deck of a Hallicrafters SX-28. The construction is such that you can't reach the underside of the tube base at all. Same deal on the PC board of this Predicta, as I recall. My handmade extender is the one with little white "socks" on its legs. Not as spiffy (or safe) as the factory extenders, but it got the job done.
Phil Nelson
