Wiper Delay Switch

The one push equals one complete sweep is very easy in the earlier wiper wiring.
It's not so easy in the later model circuits. Those will stop at less than a complete sweep and reverse back to the park position.

Yep, you would have to hold the button until the wiper passes the half way point on the winshield.
That 's what it would take in my 73 with 3 speed wiper anyway.