Hi, as was suggested already you'd need to wait about two months after neutering and just make a clear plan watch them study them each and try it very carefully, starting from short sessions, just be prepared and equipped with gloves and water spray etc please watch as many bonding videos as you can find and be emotionally prepared and confident yourself. Bonding boys is not advised generally but I believe in exceptions and in a good plan. Also bond between your pair could break and you will need to fix it slowly. But no one can guarantee how it will be as very individual. I wish you best of luck and will watch this thread please keep us updated I have some crazy plans myself but won't start before I am confident, I have lots of hope especially for boys with calm and friendly temperament who I watched from their birth. All my boys are still intact but even brothers are so different sometimes. Some of them must be separated at 10-12 weeks some of them are quite nice to each other until 4-5 months, one is nice to other males even he is nearly 8 months and his father is not a fighter as well. I've only tried very short sessions and still haven't decided which ones I'd like to bond together so going to neuter them and do it properly. But I believe some of them could bond especially those who inherited their father's good temperament and they also have very similar habits, I believe they could use same toilet etc.
I also have tons of questions do I bond them in pairs first or just try to put 4-5 together, including fixed females. Will watch your thread please share your experience with us