It shouldn't change a thing. Once he is neutered, the hormones in his system will come to a screeching halt, but the behaviors associated with being a young, intact male may take as long as 6 months to disappear.
Funny thing about dominance and submissiveness - no amount of training or any surgical procedure can change it. They are stamped in the womb with it. At or just before birth, a large rush of hormone (a brain/chemical thing) is transferred to the male puppies. Female puppies do not undergo the same masculinization. If one pup happens to get more than his fair share, he will be dominant. It's really easy to spot the dominant pup in a litter as young as 3 weeks, or as soon as they're on their feet good. The dominant pup is the playground bully; standing over the backs of the others, first to the tit, first to the food bowl, probably the first to get his hackles up. He will be this way the rest of his life.
The submissive, not receiving that same amount of hormone, will be the first to back out of a fight, belly up and show you his jewels when others approach, wet just a little when you pet him (female submissives will do this too at times) or be one of those eaters that takes a piece of food from the bowl and walks a few steps away to eat it. He will be this way the rest of his life. This "masculinization" at or just before birth has determined his fate in the hierarchy. No amount of training or attention will elevate him in his own mind.
I had a lone bitch in the house one time. I adopted her from the local shelter. I would sit often and watch her go to her food bowl, take a piece of food, walk in the other room to eat it, then return for another. She would repeat this scenario until she was 3/4 done with her meal. Even though there were no other dogs around competing for the food bowl! She was 13 when I adopted her. I deemed her a submissive for sure. The practice of leaving the food bowl like that is an old, old, eating instinct that has been perpetuated down through the years by virtually every breed of dog.
When dogs were all pack hunters in the wild, only the Alphas (and maybe a favored Beta) were allowed to stand at the carcass to eat. The subdominants and submissives had to wait until they were finished or if Alpha was tolerant, they could take a piece and leave with it, but they didn't dare eat side-by-side with the Alphas. To show you how cool and more socially advanced than we are (lol), Alpha males would often pull the soft belly parts out to the side to be brought back to an Alpha female and her young pups left in the clearing, too young to join the hunt but still needing to eat.
Snipping off Sammy's jewels will not change what occurred in the brain when he was born. The first time he struts through a pack of dogs with his ears alert and tail at 12 o'clock, the other won't care that there's a body part missing - they'll know where he stands.
Sorry I'm writing such a book on this - I've really just glazed the surface, though.
