Addition to post 20
Following is a description of how the parts should line up, and some possible solutions to get there.
A) The downrod from the pedal should be horizontally centered/near-centered, in the firewall window,and during use, the downrod should stay in the center portion, vertically speaking. The window is IMO, a generous opening.
The installed Z-bar should end up parallel to the road surface, and at ~90* to the centerline of the vehicle.
So, I'm assuming you have the engine and trans mounted in their factory location. if this is not the case, then you may have to move one or both of the Z-bar pivots, or sub in a different inboard pivot.
So,if/when you get the Z-bar properly located, and the downrod is still not operating properly; then, as a last resort,you might have to alter the window.( I'm also assuming that the pedal is in the factory location.)
B) The TO-fork should be more or less centered vertically in the window, and close to the front edge of it; to allow the use of the already properly engineered Z-bar.
You may need a different TO bearing carrier to get it there, or a different fork-pivot bracket, or even a different fork. But as you can see from the previous post, there are two different forks for the two different Bellhousings, for the two different sized clutches; namely the 10" and the 10.5. Brewers lists the BH casting numbers if you are not sure of which one you have. IIRC, there is one shorter fork(10.5) for the BBs, in the 10.5 BH; but you will lose ratio if you are forced to use it.
After you get that sorted;
The adjusting pushrod should end up about parallel to the road surface, and pushing parallel to the centerline of the vehicle, with the proper Z-bar.
C) If after all this, the pedal is still hard, then you might think about altering the pedal ratio at the top of the pedal. Or subbing in a diaphragm clutch, which is a really low effort deal, even your grand-daughter could operate it. I love mine, on account of it makes idling along at less than 3 mph possible, for extended periods of time..
I hope this helps.