Anybody own one of these?

[stusnyder]

I picked this up awhile back. Can not find any instructions or docs on it.
One plug hooks up the the hv wire, the other plugs into the harness that would normally hook to the crt. The other harness, the ones that has the clips on it, goes to the yoke assembly on the "test" crt in the case. This is where I'm stuck at. I have no idea where to hook this up to a chassis.
I think it's a cool piece of test equipment. I just would like to find the instruction set. So I'm hoping somebody got some info on this.