All I do is move my target two boards to my left (as if trying to hit the 5 pin on the brooklyn side). Another thing I've done in the past is use the spare ball, thrown straight and HARD from the one board at an angle to the backside of the two. Most spare systems would have you move your feet 4 boards right.
Shooting that spare with a full rack is very hard as you can't really determine if the ball took the correct trajectory.
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