Looking for info about the different styles of lower door hinges on 240Z. Mine was built 2/70 HLS30-01769. It doesn't have the roller & cam style hinge as seen on later Z's. It has no roller to provide a detente action. It has instead two short arms that sandwich the spring arm and limit the door opening travel. Any ideas about when the roller type hinges were introduced? I need to repair or replace. Thanks.