Overdrive 4 speed linkage

Ima thinking you have a 6-banger pedal-ratio in that thing.
If so, then you can solve your problem by re-engineering the pedal-ratio at the top of the clutch pedal. This will change your downrod angle and reclock your Z-bar slightly.

Below are the A-body forks; 67 to 76#106R on the left, #702 on the right
the 106 is for a 10.5BH. The 702 is for a 10.0.. You can just make out the repositioned channel for the pivot bracket.

CF106.jpgCF702.jpg

The 106 is 12.5 long and straight-armed.
the 702 10.875 long and angled backwards.

>below is the 484 bracket on the left, and 680 on the right.
Notice the relationship of the pivot windows to the top bolt. This adjusts the outer end of the fork up or down.
Notice also that the mounting holes are different.
The 484 is the regular, and the 680 is for the early-A


FP484.jpgFP680.jpg
you can move the forks forwards in the windows by fabricating a spacer and installing it between the bracket and the BH.

Below are the standard 67 to 76, #238 Z-bar on the left, and the early-A #636, on the right. Notice the different positioning of the arms on the tube, and it appears that th 636 has a shorter inboard lever; and possible a longer outboard lever
TS238.jpgTS636.jpg

all these changes are minor, for fitting the two different clutch sizes, and their bellhousings.
But the pedal-ratio is a major change. I'll see if I can find the Magazine article.
Found it!
Four-Speed A-Body Clutch Pedal Adjustment - Torque Shaft Rod - Mopar Muscle Magazine