Hi there.
I dont know if you've read any of my other posts, but I have two males who I bonded. I bought the second male, Max, as a girlfriend for my first, Basil. The only problem being that he was not a she, so I was forced to endure a long bonding process. They hated eachother on site...and tried to tear eachother apart whenever they met. I followed some of the advice on this link:
http://www.rabbit.org/faq/sections/introductions.html.
What worked for me (after they were both neutered, of course) was taking them on 5 min car rides once a day, 3-4 times a week. I would just set them on the seat as I drove slowly around the neighborhood, and they would be so scared of the car they would snuggle up to one another. Then, when we got back home, I took them in a neutral area (the bathroom) and let them explore eachother. I was always very attentive and made sure I was a part of the bonding process (petting, soothing words, etc). I even had a little squirt gun on hand for if one decided to bite the other a little too hard. After about 3 weeks of doing this, they becamefriends. They have been inseparable every since.
I know not all bonding has a happy ending, but I thought I would share my story. It sounds like you are off to a good start if they're not fighting right now. It might be best to have the one neutered first, just in case. You probably dont need to do something extreme like the car rides, just put them in neutral territory and let them explore eachother. That site has some really helpful information.
Feel free to pm me if you have any questions..I'll try my best to help!
Good Luck!
-Haley