@mecha, you are so right about this not easy jumping into this. I also have to say thank you to you and everyone else here that have been very welcoming and helpful.
This has been very helpful to my mental health, having something completely outside my normal life to work on and enjoy. As silly as some of repairs have been, like adding buttons, or cleaning a very poorly operating millipede trackball, some random soldering here and there, and the happiness seeing these thing working again is irreplaceable. It's also sort of meditative working on these games which I also find calming.
Is this a K4700?
So I know what parts to order.
Attached is a photos of the board on the back of the tube.
THANK YOU!!