I'd be reluctant on doing any major electrical mods to the RV, unless of course you are a licensed electrican. Airstream does sell units that run gas and electric, but I was under the impression that they ran a dedicated circuit to it. Reason I say that is when I was considering another custom built Safari SE, I was interested in the gas/electric feature. It was one of the things Airstream said they wouldn't do as it was not a variation they would do on the the production line because it had to do with modifying the wiring to a level the floor wasn't going to do.
I have an '04 and after I got to understand the mechanics of the bypass, I've not had a cold shower since. Of course, I do check the combustion and feed areas for nests, bug, webs, etc and don't take long showers when in the unit, using the trickle feature of the showerhead regualrly.