I see, I did not notice your previous post, sorry. I can't say from top of my head what the wires are good to. They still could be installed from the factory, those things were happening often in 80's - like that famous transistor glued to the top of CPU in some issues of ZX Spectrum, or the blitter fix for Atari Mega
I should have two 800XL sitting in my cellar and waiting for inspection and repair. I can't give you any schedule, but I'll prioritize the task. I've spent two weeks getting my Amstrads (CPC and PCW) up and running, so it's a good time for a change and do some Atari stuff again, and I can check the wires, or what they might be good for.
As for the superprobe - I am not sure if they're for sale, but I am thinking about designing a PCB for it, I am sure more people would be interested.