help teaching bite inhibition?

[lexio2]

After spending more time with Baxter I now believe his main problem with dogs is that he escalates so quickly from dog in my space to snarl to BITE. Koda, my sister's PB BC, on the other hand, has a very high inhibition to biting, as even tho he hates Trophy his reaction to more like dog in my space - growl - growl louder - snarl - move - dog still there - snarl - growl - snap at air (not that i let it get that far, we step in to save him from having to resort to biting... but you get my point).

Any suggestions to help increase the time he takes to go from snarling to snapping? He is still afraid of the click of the clicker, i'm working on it, but it's a slow process. He becomes VERY worked up over toys, so i don't know if i want to use that to train him for calm interactions with other dogs. All comments appreciated.

FYI - He is separated from my dogs at all times by an x-pen at the very least, if not in separate rooms.