Throttle linkage differences between 1969 and 1970

[70Nova05]

Hey all:
Does anyone happen to know if and what the differences are between 1969 and 1970 throttle linkage? I have a 1970 SS but a 1969 Rochester Q-Jet was all I could find at the time. 1970 uses a throttle cable, and I picked up the correct throttle bracket for a 70, however I can only get about 3/4 throttle out of this setup. Should I be using a completely different setup?
The cable is not super tight, and only has about a 1/16 inch of slack in it. It just won't pull the full distance to open the secondary's all the way. The pedal seems fine, hardware in good shape, and it goes all the way to the floor. There is no slop at the top of the pedal.
Any ideas would be very welcome.

[Blue Bowtie]

You can either lengthen the arm on the pedal or shorten the center distance at the carb belcrank.