I read through this thread again this morning--those feelings of sadness, inadequacy, and "what have I gotten myself into" came flooding back. The struggles I had getting him into a collar, changing a collar, were epic. One of the reasons I am so happy he hasn't needed one in a while is because I don't want to revisit those battles. He still won't let me touch him, except grudgingly on the top of his head--sometimes.
We have come a long way! I'll keep working to gain his trust and make sure he gets the best care I can provide.
@Blueberry I started training Opie in the same way I started training the budgie boys, Jelly and Juju. I started by training him that the sound of the clicker means he gets a treat. So: click, treat; click, treat; etc. This does not take very long at all for clever birds. Once he had the clicker idea down, I introduced the target stick. I use a plain chopstick. I hold the stick about 1 to 2 inches away from his beak and just below his eye line so he can see it. I have found that a curious bird will reach out with their beak to investigate the stick. As soon as he 'beaked' the stick, I clicked and offered a treat. My first day is usually just that much. Once he had the target stick down pat, I would ask him to lean and take a step or two to reach the stick, 'click', treat. After just a few days, I was running him all over the inside of his cage using the target stick. When he had regular out of cage time. I could get him to travel all over the outside of his cage using the target stick, too.
I have used target training to get him to 'spin', step up on a rope perch, and step onto his play perch. Targeting has been a way for me to ask him to do what I would like him to do. It is absolutely voluntary, though. If he is not in the mood, then he is not in the mood. I try again later or the next day. I'm currently working on 'touch' in an effort to get him more comfortable being touched for exams and hopefully getting him in a collar again if need be!