I just read a thread the other day about this that had some very good link to other sites addressing this very problem. Someone cleared my history so I couldn't find it, but this is what the person suggested works:
1. Be the top 'Rooster' in the chicken yard by dominating the roo. To achieve this you have to be bigger and badder than he is. This does not mean you have to whoop up on him, but take charge. You are bigger, use YOUR wings (aka arms) and go toward him and scare him away. Do not let him eat or drink until YOU say it is okay. Ladies first, then let him if he behaves. Let him know with NO DOUBT that YOU rule the roost, not him.
2. Pick him up and find a place to set him down that is waist high. If he struggles as you let him down, pick him back up again about face level to you. Slowly lower him until he can be set down without struggling or flapping or anything. If he can do this, apparently, you are doing well.
3. If you can't get close enough to him to do #2, use water and spray him. I hear super soakers are very good for this.
I wish I could just find the site and paste it in, but I don't know where it is. I do know the two roos she was telling about were Zeus and Thor. Zeus was a spoiled and nasty boy, and this owner had him so straightened out that he isn't even allowed to mount a hen in her presence. Pretty niffy idea for establishing who is in charge.
I hope this helps. One thing I do know, animals can smell fear, and if you are not willing to take the upper hand and be firm, then you can foget rehabilitating this little man.
Good luck.