This is from my Bally Knockout. The outhole relay operates the score motor and thru a ball index relay switch will advance the ball count unit either two steps thru a normally open #3 and #4 score motor switches during a one player game or one step thru a normally open #4 score motor switch during a two player game. The outhole relay then completes the circuit to the outhole kicker solenoid thru a normaly open #7 score motor switch. The 1st ball is returned to the shooter and the game is now set for either 1st player; 2nd ball or 2nd player, 1st ball.
Hope this helps.