Hello Jacob :-)
Unfortunally for you the 10 pins header near the mouse ports is a feature connector with various signals fed to Lisa :-( as you can see below :
"Mystery" Header (courtesy of Dave Haynie)
"There is a 12 pin header (DIL, J975) near the mouse ports. This feeds the 'extra' shift register in Lisa. Unlike OCS/ECS systems, which simply multiplex the four quadrature signals from each mouse port with one another, the AA systems serialize all eight bits of mouse data. While they were at it, the AA designers added a second 8-bits to the mouse port registers. These don't hook into mouse logic or anything, but they can be read by the CPU."
So if you made a shortcut to these pins, it can be necessary to send the motheboard to a repair service like
www.amiga.fr per example. (BTW as all the chips are surface mounted it will be obligatory).
