Need pinout / lead id for trackball from mx11800

[Oqsy]

I'm dissecting my mx11800 and need some advice with the trackball.  The old trackball device is DEAD.  That being the case, I'd like to take advantage of that location in the case for another trackball or mouse-ish input device.  

The bottom line is, there is a little connector with a black, yellow, white, and green wire, and a separate black ground wire with a terminal for a case screw.  Can anyone help me with identifying which wires correspond with which pins on the PS/2 connector for the trackball so that I can integrate my solution into the existing cabling, etc?  The trackball unit in these cases that I've removed is: LOGITECH M/N: T-SBC12-CPQ if that is any help.

Thanks for any leads.

[Oqsy]

I found someone on logitech's message board that had the power ang ground identified, but that still leaves clock and data... bummer.

The more I think about it, just using a USB device and adding another hole in the case for the cable next to the existing cable might be the simplest answer.  I'd end up with an odd looking set of cables, a double PS/2 *AND* single USB coming out of the case.  Maybe I can figure out a way to integrate a usb hub / blue cube into the case and only have a single usb cable coming out of the back.  Oh, this is going to be a great summer!

[Oqsy]

Definitely worth looking into.  I'm almost certain that the wiring for the trackball is independent of any keyboard wiring.  It goes directly into the larger insulated cable with no signs of splices, and the keyboard controller's cables enter a bit higher up, again with no sign of splices.  This model trackball was used in laptops and other scenarios, so it's very likely that the wiring was kept independent to make the unit a bit more versatile for other applications.  

Your suggestion for keeping the wires and just swapping plugs really has me thinking about the possibilities here.  I'm pretty sure I've discussed the direction I'm heading and what my goal is as a replacement for this trackball (in the #geekhack chat room).  I don't want to give too much away since it's going to be a bit tricky, and it will also be very unique and I'd like to see the idea through to fruition before someone else does it quicker, easier, and better than I do.    

When it's all done the board will have DIY cherry reds, (already assembled, i'm missing ONE brown spring!  DOH!  No scroll lock for now.  Anyone have a spare?), a custom color scheme, and some structural changes to make it more "solid" (no, I'm not melting lead).  This will most likely be the beginning and the end of my attempts to customize a keyboard to this degree...  we'll see how it works out.

[InSanCen]

If I had one, I'd trace the pinouts. If it does indeed go straight from the trackball to ghe main lead bundle, it should be fairly easy.

[InSanCen]

Actually, right, that would be easy. We know the pinout of a PS/2 plug. Multimeter to the rescue?

Pretty much. Continuity should do the trick, as you rightly say, we know what the PS/2 end is pinned up with, just wait for the beeps at the other end.