Hard to say as you can't really see which pins the wires connect to, and you can't see what's happening at the other ends of the wires.
The pictures looks like yellow connects to pin 26 and white to 28, which are both part of the 16 bit data bus. Doesn't really make any sense.
If you can list which wires connect to which CIA pins and what's happening at the other end, i.e. which wires get joined when the switch is in either position, I might be able to give some suggestions what it's for.
A tip for taking photos when your camera isn't so flash or your photography skills are just crap (like mine) is to use a flatbed scanner. Produces surprisingly good results.
A bit tricky when you're trying to take a "photo" of something big like a computer though :-)