[LMH]

On standard street leaf spring cars, the washer bag is hanging from a mount on the aluminum panel directly ahead of the brake fluid reservoirs. it uses a Ford electric washer pump to pressure the sprayers when energized.
Did comp cars use the system from the street car... I don't know. A guess would be in the interest of saving weight, it was removed and the jets left in place to cover the holes in the body but I really don't know. If the windscreen needed to be washed, that can be done at a pit stop.
Larry