Hi
As long as the boys don't fight, please leave them. Over time, they will produce a calming compound in the constant presence of sow pheromones; especially when the girls are in season. Your boys have just entered adulthood and are only just starting to come up to the prime of their lives.
Please be aware that by housing the sows above the boars, pheromones from sows in season drift down each time. For this reason we usually recommend to house the boys above the sows, as it takes a really strong strong season for pheromones to create a proper cloud.
However, in the absence of fights, you have to weigh up whether it is better to leave your boys as they are or risk it with a change of territory and a re-establishment of the group in their new territory with all the attendant dominance behaviour. Personally, as far as boars are concerned, my advice is to please not to rock a boat that is not in any danger of capsizing.
The overproduction of semen fluid will also gradually settle down once they get further into adulthood. Neutering won't change semen production, masturbating into their own mouths or social dominance behaviours. All that neutering does is remove the ability to make babies.
You may find these links here helpful and thought provoking:
A Comprehensive Guide to Guinea Pig Boars (see especially chapters 2 and 3)
Reacting to group or territorial changes: Dominance and group establishment/re-establishment
Neutered / De-sexed Boars And Neutering Operations: Myths, Facts and Post-op Care