I'll try..........
Picture a side view of a car.
Imagine the front tyre contact with the road and a vertical line up through the centreline of the wheel.
Imagine the CofG of the car (height mainly - fore/aft lets call it the centre between the front/rear, but does not really matter)
Now imagine the front and rear pickup points of
BOTH the upper & lower
front wishbones. They can be any distance you like fore/aft of the wheel centreline - it does not affect the geometry.
If these points are parallel to each other & the ground - no anti-dive.
Two ways you can arrange anti-dive (parallel pickups or converging).
Converging - visualise a third point which is where a line between the front/rear pickups meet the vertical centreline of the wheel (this is actually the notional pivot point of the front wishbones). Draw a line from here back to to the CofG from the
upper & lower points (the lines
converge at the CofG). Then place the front/rear pickups each side of the wheel on this line. This is 100% anti-dive.
To get less anti-dive; now move the converging point vertically halfway between the ground and the CofG and re-draw your lines through the upper & lower wheel points and move your pickups onto this line - 50% antidive and so on.
Parallel arms - I THINK in this case you tilt the line of the arms together (keeping them parallel with each other), and project your line from the tyre contact patch to the desired distance from the CofG.
I wouldn't be surprised if you could use diverging wishbones projecting a point ahead of the car then back to the CofG - AFIK this hasn't been done.
I don't believe the pushrod has anything to do with it. When the brakes are applied the force is transmitted from the tyre through these arms to the chassis and the dricetion of the arms affects the way the forces react with the CofG.
BTW anti-squat uses the same trick in reverse