I'm wondering how much experiance you have with breaking. Do you know when something is beyond your ability and you need to send him off to a proffessional?
Rearing is as dangerous as it gets and you do not want this to become a habit at this early stage.
My 4yr old I started breaking when he was 3, I admitted defeat after some rather spectacular explosions in longreins that I just couldnt hold and couldnt seem to get him over, I'm not experianced enough to deal with his issues myself, so I sent him to one producer and she sent him back as she couldnt deal with him.
I then worked with him for a while whilst I was sorting out arrangements. He broke my shoulder when he exploded when I put a saddle on him (despite the fact he had had a saddle on many times previously). He has since gone to anouther Producer who within a week has him longreining with no problems and is working on the saddle issue.
I realy think that if this horse is rearing you need Proffessional help.