Just do as if you were making up a starter, boil up some dme, cool it and add the dregs of both bottles to it.
Flaming the lip of the bottle is a good idea, or spraying it with starsan.
If you don't plan on drinking both bottles in one sitting, I've been successful with sanitizing a fresh cap and re-capping the bottle, and leaving it for a few days in the fridge with about 1/4 of beer left behind. Just make sure to give it a good swirl before hand.
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Revvy's one of the cool reverends. He has a Harley and a t-shirt that says on the back "If you can read this, the bitch was Raptured. - Madman
I gotta tell ya, just between us girls, that Revvy is HOT. Very tall, gorgeous grey hair and a terrific smile. He's very good looking in person, with a charismatic personality... he drives like a ****ing maniac! - YooperBrew