I do believe Django could be #1. He used octaves before Wes and was an excellent rhythm guitarist. Even his improvised solos were excellent. There is the story that Andreas Segovia heard Django play a beautiful piece and demended the sheet music, though Django had just improvised the whole piece. I do believe a moderater on a different list said this was a true story. Montgomery's influences were Reinhardt and Charlie Christian. The man practicully invented an entirely new style of jazz guitar technique which is what we know as Gypsy Jazz. Just ask Les Paul, Joe Pass, Charlie Christian, Barney Kessel, George Benson, and Wes Montgomery who their influences were and they'll all have at least one thing in common. Django Reinhardt.
By that stand, Charlie Christian could easily be No 1. He probably has more direct influence on those names than Django, other greats like Grant Green also were hugely inspired by Christian. Montgomery is certainly the biggest influence on George Benson. For me, Wes has the edge if only because Gypsy Jazz appears to me, to be a narrower style of music.
But like places 2-7 on the rock list, splitting these guys can only be a matter of personal taste. I certainly wouldnt argue if the placings were the other way round.