The same thing just happened to a friend of mine. He had a 66 Dodge Coronett with eight and three-quarter in it. He bought new alloy axles For is 66 rear end only to find out when he pulled the old axles out they were longer. Somebody had put a 71B body rear end in the car. Now he’s got axles too short I had to go out and buy a new axle housing to match his new axles.