What year did they start using them? My 74 Dart Sport has them. I'm thinking they started in 73? I'm going to look at a pair of 72's, if they don't have them. I'm looking to lose the weight. (Car will have a roll bar.) The 72's are in better shape than mine, too. While I'm at it, what do they weigh? Can they be removed? They appear to be built into the seam where the inner and outers are assembled. If so, I guess it would be easier to weigh the entire door and compare them.