He goes in a plain jointed loose ring snaffle. My goal is to keep him in shape during the winter, and refine our communication. Maybe do a little baby dressage at fun shows if the spirit moves us. I've been learning how he is used to being communicated with (it seems like he's had a lot of Clinton Anderson style work done with him) and now it seems time to teach him a little of my language. I kind of view it as two people each speaking a different language - I've been learning his, now he learns mine. And in my mind that means accepting light contact, and differentiating that from a halt. I'm not trying to force him into a frame or make him a grand prix mount. Just trying to better our relationship, and keep us both learning. I can't ride him exactly like he is used to being ridden, because A. I don't know much of his training history, and B. I don't know squat about western.
"Here? It's like asking a bunch of rednecks which is better--Ford or Chevy?" ~Deltawave
I know many horses that go both Western & English, it's really not that difficult a concept for the average horse ...
The easiest (fastest, simplest ) is to find a trainer that knows how to do this & take weekly lessons or even a lesson every ride for the first few weeks - note that twice a week lessons (even if you only lesson for 30 min & then "practise" for another 15) will yield tremendous progress in only a month: consistency at every ride is the key.
Lunge work can also be very effective but it's important that the human be trained first
I like what you said about learning each other's languages. And I think you know a lot more than "squat" about western since you are learning his language and he has already taught you a lot. All the things you said in your OP that he is telling you. Those are things you are learning about his western training.
I don't think there is just one way of training that is "western." Western riding has as many disciplines as "English" riding and they don't all translate across each other's lines. You talk about some dressage-like arena work, well, I suggest checking out the web site of the Western Dressage association. They may have some really helpful tips. Here is a link to them. They may have a chapter near you.
My boyfriend bought a quarterhorse that was trainied western pleasure. He seldom came out to ride the horse so I started training him in dressage. Showed the horse in dressage, training level, he was always in the ribbons. Well boyfriend came out every now and again and would ride him western. The horse knew the difference and could easily switch from one to another.
My guy was a reiner and didn't really get the concept of dressage/English contact. To be honest, it was a long road and I still to this day ride him in a western bit. (Except when we show.) For me, I started by asking him to collect up with soft contact at the walk and then stretch back down. What helped him was actually seeking the bit. I then advanced this concept once he understood at the walk.
Whatever you do, don't haul and yank on his mouth. That'll set you back big time. My goal was always soft light contact. I can still ride him western and he totally knows the difference.