Well, when we introduced Max (8 at the time, unnutered Male, (another story also...) to MacDuff a new golden Retriver he wasn't happy at first. But we did introduce them on neutral ground. Then we just made sure that both got some extra special attention and in no time they were "buddies". We recently got Spike (who was unnutered for 2 weeks with Max) (Our Vet was more concerned with this relationship because Max went through a long grieving period when we had to put MacDuff down..Brain Tumor!)Spike was 7 months old and Max is 15. Again, we had them meet on neutral territory and they have been pals ever since. We made sure that when we would give them each a treat that we gave Max his first then Spike.
Good Luck!!