I've been told by Dave Smith at Pro Trans to use the Buchillion (SP?) kick down cable instead of the other brands out there. On your deal if you have the 1965 kick down linkage I would try that first though, I've only seen two different versions of the stock kick down linkage on B body cars. A one piece single rod that is adjustable on one end and a three piece set up including the rod from the carb to the throttle cable bracket
The three piece set up has bell crank on a screw in stud that goes into the tranny case with a rod from the bottom end to the kick down lever and another up to the bell crank on the throttle cable bracket that hooks onto the rod to the carb. from the top bell crank
I had two 1965 Coronet, one 440 and one 383 500 4 speed car, the 440 car had no motor or tranny in it when I bought it and I can not remember which parts I put in that car to sale it, 440 motor with a 727 I think