Desiree,

i know a couple who have 2 male OP and they get along just fine.

the youngest one is about  4 years old (they raised him from a pup) and the oldest one is 12 years old.

the old one gave his dominant position up to the young one without much trouble.

but the young one is still very confrontational with other male dogs.

i just think it's a case of making clear leadership for the dogs and let them settle a few things for them selfs, so that between them there is also peace.