Let’s take another look at the console. There are several boards inside, but this is the only one which deals in custom Symbolics protocols (as opposed to the widely-known intricacies of operating a black-and-white CRT.)

The rough annotations are my own. Click on the pictures for super-size (~10MB!) images.
Once again, the Phase Encoded Video decoder board:

A: [...]

The machine does indeed power up and run:

But this is not enough.
The console is a museum piece. While a Lisp Machine circa 1986 might last for a reasonably long time between repairs, a CRT of the same vintage likely will not. Moreover, it is a pain to have around, even if it were indestructible. Wouldn’t [...]