mouse help/hack

[h_2_o]

I'm looking at using a mouse for some possible modding. what i want to do is use a mouse in this manner

http://home.comcast.net/~maccody/robotics/croms-1/croms-1.html

for possible measurement, however i want to use it while connected to the pc. the other problem i'm having, well i'm having more than one is finding a way to use the mouse and not have it interact with a pc while using the optics in it. if anyone has any help/hints/suggestions it would be appreciated.

thanks