Which one is the older because youngsters can start trying to be top dog. We didn't have many problems with our males but we did have one we kept from an all-male litter (Sods Law when not wanting another male to keep). By the time he was aroung 18 months he decided to have a go at his older uncle (who had been used at stud but not so with the younger boy) and the fighting became increasingly more serious, always started by the younger dog and always vs his uncle despite having 2 old males too. Normally I'd try to get them to settle their differences and to that end, I hoped, I put them together in the outside pen, knowing that if a skirmish started I could use the hose!! What did they do ..... sat with their noses together against the gate until I decided this wasn't going to work, and let them indoors again. Later in the day, another skirmish.
After a lot of thought because when we select one or two, to keep, they usually stuck, I contacted a girl, with two bitches, who I knew might be interested in having him. She was and I co-owned him with her until I made sure he was going to be okay. We went to see him a few months later and although he 'acknowledged' us, he turned back to what he was doing!! Much as I missed him, the good part was peace returned to our small pack - and his uncle was relieved I suspect.
I'm afraid you may have to give this some serious thought because, much as it's normally said that males tend to fight to mate and bitches to survive, fact is these two may never be reliably able to be left together. And I don't know about you, but I'd not want to live with two dogs that have to be in different rooms, to maintain peace.
