Technically you could bypass the interconnect board and run the optos directly from J2.  Not sure if any fusing or resistance occurs on the board that would be of concern, without consulting schematics.

You'll also still need to find the feed wires to hookup to J2.

Most people would consider it a hack though.

For testing purposes you could hook up J2 with test leads and find a suitable place to input the voltage along the black-yellow/grey- yellow wires going to the optos.

Also please see my edit in previous post if you haven't already.