Looking at the 74 parts manual, since I don't have a 73. The only difference in the pedal itself is manual/automatic trans. Power or manual brakes doesn't matter. Linkage has setup that reduces leverage into the booster, so if anything you'd have too much brakes without it.
I suspect the orientation of the pushrod to the mounting point on the pedal arm is different between the two bc the mounting point on my pedal arm doesn’t line up so I had to do some fabricating to get it to even work. It’s not right. It’s like two inches above the hole in the pedal arm and about three inches away from
It. I knew it wasn’t right but until now I didn’t know what was wrong.
I think I can make it work if I can set the plunger right according to the instructions I have been given here.
