Yeah regardless of having anti-seize on them or not the block warping around them from the heat always makes them a chickenfucker to get out. You need a special type of socket with sharp edges inside that spiral down....I forgot what it is called. It digs into the head of the bolt as you turn it to back it out so you can get it out.....that's probably about your only option there. BTW, those headbolts are expensive as fuck from Honda lol.