We are looking at a Cat M40D S/N 4WC. It has had a Transmon Engineering operator key pad with impact override system retro fitted that someone has tried to rewire to bypass. Subsequently on arrival at site the truck was dead and the truck wiring is in quite a mess. We would like to return the truck to it's original ignition key switch system but aren't entirely sure which of the mass of chopped about wires we need to fully restore the truck back to original. We can get the truck running ok for the customer using the isolator which has been fitted in place of the ignition switch, but aren't entirely sure it's 100% correct. Would anyone have a wiring diagram of the ignition switch circuit going back to control panel.