Question: The horse moves well, gaits well, but am not happy with the head set for the show ring.  I would like to get the head elevated, breaking at the pole, with a nice tuck on the chin.  I would hope to accomplish this in the bosal, prior to biting. 
 
 

This is a typical problem it takes a little work, but should be easily resolved. First you are right to want to work this through in thejaquima, I would stay away from the bozal and go to the barbada (  chinstrap). Start with walking flat and straight asking your horse to
flex to the inside while walking. You want to ask him to give to the inside and also keep contact on the outside line so as he gives to the inside he must also give in toward his chest slightly. Normally young horses will want to stop or move to the inside that is ok just ask a
little then continue walking relaxed. As he loosens up and you get more conformable doing this you can work on this at the walk, corto, and largo. 

This exercise will help to loosen the pole, neck, and shoulder.

Now also work on walking circles nice and relaxed asking for the same give with a nice bend to the body, and also asking him to give the inside shoulder. With the pasos these are the most neglected exercises.You want him to be able to work shoulder out but the important one is shoulder in making sure he lifts the inside shoulder and moves is over
as opposed to dropping the inside shoulder. If you continue to work on getting him loose in the pole, neck and shoulder he should start to setup in short order. Just do most the work relaxed and easy don't give him the opportunity to fight.

Terry