Rehoming my big goofy boy. (Vandalia)

I'm having to rehome my lovable, big, goofy boy, Sampson (he's about 65 pounds) He's usually friendly with other dogs and even strangers, but he's having conflicts with our house-mate's dog and we can't be having that.
He seems to get along with dogs and people even when I take him to the vet, so I think it's just a territorial thing with the other dog being older and already established in the home and he's the younger "challenger" to the home.
So he is scheduled be neutered on the 16th of April, but if someone wants to give him a home before then, I'm okay with that.
I'm just trying to avoid further conflicts between the dogs, so it might be best that he goes to a household where he's the only dog.
Text (SMS) or Email okay, please no voicemails.