Where would you aim to pick up the 1-2-4-9 spare?

you should basically be aiming the same as you would for your strike shot. but because of the 9 pin you might do a bit better if you hit the head pin on the right side a bit. so stand where you would for the strike shot and move over 1 (maybe 2, but most likely 1) board to your left and give it a try.