1966 Zenith console stereo

[Electronic M]

For a unit like that a reel to reel would be appropriate too, and would sound better than the 8-track...

The transistor swapping is a good idea. That is how I found a bad chroma amp on my Zenith hybrid TV. The three chroma amp transistor sockets were all oriented the same way so swapping was a nobrainer...Granted they were covered in big heat sinks so no dots were there to be seen.