OK what machines were built in '75, '85 or '95?

All the very best with the project.  I hope you succeed where other Aussies have failed.  

The kit idea sounds interesting.  Just a thought but perhaps you might consider different levels of kit e.g. beginner and experienced.  It would be a shame for your machine to cop a bad wrap just because a Noobie couldn't put the machine together properly and either damaged your reputation or the machine.

Again though Mike, all the very best with it.

Intention with the kit is flatpack cabinet, all electronics assembled and tested including wiring harness - all mechanical assemblies built and tested.

Basically assemble the cabinet, screw in the boards and assemble the parts to the playfield.

All of this could change as things progress however.