I think the 78 has the sunroof motor in the trunk, up by the trunk hinge. If so, there was a tool in the tool kit originally that allowed you to manually turn the mechanism in the trunk. It was a screwdriver type drive with a nut body, only about an inch or an inch and a half long. Later cars do have the motor in the headliner area though, but those can be driven by an allen wrench in the center of a nut which is accessable through a 3" X 1" (?) trapazoid shaped access cover up by the sunroof switch. As a matter of fact, if it doesn't have the access cover it is almost certainly in the trunk. Mike