Cables for oval faced speedometer have a round, flagged end on the drive end and a .124 square end on the speedometer end. These use a 1/2" dia. housing. The cables for the round faced speedos have a .104 square on each end, they use the smaller diameter housing. You will some times find that someone miss matched the parts and it is not correct. Snyder's used to sell special cables that had the ends made so that you could use a round speedometer with a oval type drive, and vice versa. I don't know if they are still available. Easiest way to correct is to change the shaft in the drive on the torque tube to match the speedometer type, then get the proper cable.