To add to your "names" of inspectors, I located one stamp on my Oct '65 Metuchen GT in the same position as yours on the right inner fender. It was in the same format (and appears to be the same font), "Paint OK Conger", and in yellow. I have seen one other location than those you've outlined, the underside of the hood. It was another '66 Metuchen car that belonged to a friend. It was on the underhood bracing in the center and in white. It's been MANY years and it was either "Paint OK Martin" or "Martini". I haven't located any other inspection stamps on mine yet.