i called shaftmasters and they said they can make me a driveshaft witht the slip built in . it will be aluminum and have an adapter to bolt to the flange. i need to send the flange and they said it will be about $650. so i canceled my order for the factory challenger driveshaft since it has been about 2 weeks and hasnt came in yet anyway. it was going to be $380 plus the price to have a shop rework it to work in my car.