Practice blocking the bite: elbow flap that meets nose swinging around for you, arm raise so nose runs into arm. Do these as if you're not reacting to him at all, so he thinks that by swinging at you, he's bonked himself. This means, don't even look at him when you block, just act like you're doing your "thing". DON'T get mean or mad, don't get retaliatory, because that means that he got a rise out of you & won the game. You can also do jumping jacks, when he goes to climb over you/ram you aside, again, impersonally, like you just got it into your head to do some jumping jacks.
A horse with this "horsenality" is not bad, it's just a mouthy personality. He needs lots of interaction. He needs you to play with him (keeping yourself safe) & play a bit harder than he likes, e.g., when he starts to nibble on your fingers, rub his muzzle, pull his lips, etc., but a bit harder than he likes, so it's HIS idea to retreat. Get him busy doing other things as a replacement for his antics,(he's bored) & they'll evaporate. Good Luck!