My 5 year old son has no respect for authority. Help?!?!?

I have two sons. My oldest is 5. I take him to a developmental pediatrician, a psycholigist, and an occupational therapist. When he was 3 he was given a psych test to see if he qualified for a gifted school in my area and his IQ was 131. His last IQ test he got a 155. He taught himself to read at 3 and now reads at a 5th grade level according to testing. Every specialist has ruled out Autism, PDD, Autism Spectrum disorder, and a few are on the fence with ADHD. His father and grandfather have ADD. I am an at-home mom. When he was 3, my son escaped his preschool so I withdrew him due to safety concerns. When he was 4, he attended a preschool a few days a week and within a month, he was lashing out at teachers, even kicking a few. When he started Kindergarten this Fall, he would flat out refuse to do the work in cl and he spent most of his day in the principal's office. The school then arranged to put him on a 508 plan, which would allow him to go to Special Ed part of the day. I also need to mention that my son has a lot of anxiety regarding very specific things. Trains and noises ociated with trains, the "happy birthday song", when someone says "cheese" as a photo is being taken. He goes into intense rages at hearing these things. He is a very outgoing, social boy. He has no respect for adults, teachers, or us a lot of the time. For discipline, we do time outs, removing things like toys, priveliages. At the moment, I am homeschooling him because I thought him being in special ed all day was not going to grow him as an individual. With most kids I have seen, once they get into a routine and learn what is expected of them, especially at school, they eventually comply. With my son, it gets worse, no matter what the environment. I am exhausted and feel as though I have no where to turn. No one knows what is going on with him. Nothing I've tried works. More background: His father and I have been married 8 years and live together happily. We do a lot as a family. Neither of us drink or smoke and we are somewhat religious, although we don't go to church. My huaband and I are both intelligent and the most successful method we've tried is "parenting with love and logic". My son has also had progress charts, sticker charts, "mom bucks" to earn for good behavior and to be taken away for poor choices. We have started him in Tae Kwondo to build skills in self-discipline and respect, which he likes. I so look forward to any tips or advice you can offer. I feel as though I've exhausted my options. Thank you!