I lean toward the ALPHA behaviour as well
and I have 3 alphas in my pack, not including me, so it is constant interruption and correction. You lead by example, and everything is always alright. They take their cues from you. I do not permit any alpha behaviour toward me. None. No paws on me, no standing on, against or over me. That puts me in submissive posture. No. Strong correction (my BlindPup has a very alpha personality and carries her wigglebutt tail held high constantly) When she paws me (places her paw on my arm, thereby 'claiming' me), I grab her paw and she does not get it back until I say she does.
I have 3 lethals and two lab mixes in my pack, and the ONLY way a handicapped pack can work is with strong leadership. They adore me, they obey me, the deafblind will seek me out with a nose and he is a cuddler. They see me through my hard times, and I love them. More than words could ever say. But I am always the leader. Anything else would create very undesirable behaviour that would be unlivable and certainly unacceptable.
Next time he gets over you remove him with a sharp NO. And put him into a sit. When he does, lots of rewards, whatever you use for training that rings his bell, toy, PRAISE, a treat.