70 only, take it out & have a look at it, take the snap ring off & slide the pin back, it is holding a twisted spring so if the spring is broken it won't try to untwist.. I have found a few that broke right at the end, if that happens you can rework the spring, if it broke in the middle it's a parts seatbelt.. But some C bodies used the same design so you might find one of those....