Thank you for the info.
Will strip old switch out and take copious photos. I may end up re-using the off/on/on rocker with it's correct contacts in a none broken housing, if new switch doesnt have the correct contacts.
In "Park I can get a full house of lights, but in position "on" or 2nd "on" position I don't get the tail light, not got engine running yet to tell about 12v headlight, bit strange.
Am I right to assume its the grey wire that is the 12v DC feed into switch?