Try setting the jib all the way down and then moving the pick up point up the clue board. I'm assuming you know how to work out the right sheeting angle using the upper and lower wind indicators. If you find you're not getting enough leach tension slowly move the jib up until you reach the right point. Thinking about it I'd set the tack height so that your jib is on the second top clew hole. This will leave you a little scope for on the water adjustement.