5. When I started to lunge him, he would turn into me constantly! I would tap his inside leg and when it went over, I would drive his hind foward. That worked to get him to lunge for a little but now, he pushes me out of the way with his head when I go to tap his leg, or circles around me so I can't tap his leg.
What kid of line are you using? I would use a rope halter and a thick and heavy yachting rope line. With this, you have more control of the rope and his head, and it is harder to ignore.
With a rope like this, you can push him out from a distance by wiggling the rope in ingreasingly large waves. It wont hit him but it looks scary enough for most horses to get the message.
When he comes into your space, you need to push him out with equal force that he is invading your space. It sounds like he is being fairly agressive and threathening, and that he has figured out that you will only hit him on the feet? When you say that he is pushing you with his head, do you mean that he is actually almost on top of you?
That is very unsafe, and you will need to get a lot toughter on him. Keep him at the end of the line, and take any slack in the line as a sign that he is invading your space, and push him out until he is at the end of the line again. I would also invest in a longer whip, so that you have adequate reach.
It is OK to give him a whack elsewhere than just the legs. If he is running at you even after you ahve wiggled the rope, I would do the following:
1. Run towards him with a predator look (usually this in itself is enough because they are used to the lunger being fairly still. Tense your body, crouch down slightly and stare him down)
2. Run and whack the ground directly in between you, making a hard sound
3. Smack his legs
4. Smack his chest
5. Smack the leadrope right under his chin
6. Smack his nose.
Do not wait for him to get into your space but meet him halfway, this shows him that your boundary ends only at the end of the leadrope, and that you are not going to let him disrespect you. This is a situation where you can't afford to loose, and therefore you have to be tough even though it feels nasty. If you let him walk into you today, tomorrow he might run over you and kill you. As I mentioned earlier, if he rears, whack his stomach and make him back up by any means.
5. With her other horses all it's takes is a jerk on the halter for them to stop, but that doesn't phase him. When I really crack down on him, he'll walk VERY slowly in a circle and then just turn his butt towards me and walks off, pulling the lunging line right out of my hands. I jerk the rope hard when he does his and he spins around, head very high, and walks towards me. Then we start all over again. This happened 20-30 times last night, jerk the leadrope or making him backup does not work.
With a heavy yachting rope line, you can stop the horse by wiggling the rope up and down in increasingly larger waves (promise level: rope hits the horse on the nose).
Does he know how to yield his hind quarters? If he knows it, an even better way to stop is to diengage his hindquarters (yield them out so he faces you) while putting the hand that holds the line up so that he stops and does not walk in. If he starts walking in, wiggle the line sideways in ingreasingly large waves. The movement is sideways because you want him to back up staight, so you are speaking to both sides.