63 was the last year the out of the box SS springs fit. After that the front segment is longer (as is the car, the carpet etc etc) using the extended hangers destroys the instant centre of the car much like shortening a set of ladder bars would and moves the instant center back in the vehicle (that is not good) They will work but their effectivenessis questionable at best SO we take the 64 and later main leaf and dissassemble the SS springs and after removing the main leaf we bolt the rest of the spring pack underneath the stock 64 leaf. (If the main leaf is rusted we get a new one made at the spring shop.) For real heavy cars like my 74 Charger (4150) we cut the ends off the SS main leaf leaving it as long as possible and remove the second leaf down instead and then bolt the whole assembly under the cars main leaf. For real hig HP in these heavy cars we get a main leaf made out of the next thickness of spring material (ie 1/4" to 5/16" ) That does the trick well. We are after ultimate traction which is no perceptable wheelspin and front wheels up on a good launch. More often than not we succeed. Sometimes even on the street. Hope this will help someone. It sure works well Don [Non-text portions of this message have been removed] ---- Please address private mail -- mail of interest to only one person -- directly to that person. I.e., send parts/car transactions and negotiations as well as other personal messages only to the intended recipient, not to the Clubhouse public address. This practice will protect your privacy, reduce the total volume of mail and fine tune the content signal to Mopar topic. Thanks! '62 to '65 Mopar Clubhouse Discussion Guidelines: http://www.1962to1965mopar.ornocar.org/mletiq.html. b7yoMz.