I completely understand the idea that it would be better in some way. I mean, my optical mouse works a million times better than any ball mouse I've ever used and I'm 100% sattisfied with the $50 I spent on it...

It was back when they first came out.
But, and there's always a but, you have to realize that the mouse optics won't be operating in the same way they were designed if you hook em up to a trackball. First off, they are designed to
read only flat surfaces, and second, they are supposed to be on a non-shiny surface preferably with some sort of pattern, just a few things that a trackball is definitly not.
Anyways, if you realy want to experiment with this I'd suggest going the route of optical trackball for the pc and take the guts out of that. Just look for a trackball in your friendly neighborhood bestcircuit that has a red ball with black spots. You may have some luck with that, but i'm certainly not guaranteeing anything.