Sure two males can get along. They will, however, fight over a female, so keep em clear. I had four unrelated males living together before neuter.
Gliders fuss with each other, its normal. A real fuss will be very loud with lots of endless crabbing and even that isnt usually a tear down. With that said, gliders are creatures such that it only takes a second for a life-threatening wound to happen, but this may be true of most species really. In a real fight they will clamp together and roll around fiercely biting.
You just have to watch them, get a feel for them and make a call.
My males cage gets all in a fuss when I serve shrimp. I dunno why; I guess they like it so much. But most of them run around with shrimp in mouth and crabbing and crabbing probably trying to find a space away from the others to enjoy it. Its all crazy sound but harmless and normal for these four critters.