The Dolphin shouldn't (and probably won't) be able to mount six guns at once. Historically, new Dolphins arrived with four guns fitted, two vickers and two lewis pointing up at an angle. Most pilots removed both lewis guns, while some retained one. 87 Squadron, removed the lewis guns from the cockpit and mounted them on the lower wing firing forward but these couldn't be reloaded in flight.
The real beast is going to be the modifed Bristol F2B F.II that can be fitted with an extra two lewis guns on top of the wing. That gives three guns firing fowards and two firing backwards! The Albatros D.II should be pretty interesting too with an overwing mounted 20mm Becker cannon!