Clamp - i figured it was something like that. Have your tried rigging that with a single Mathellini?
http://www.bhphotovideo.com/c/product/301945-REG/Matthews_420210_Matthelini_Grip_6_End.html
Various things that plug in - makes sense.
GoPro - what is your strategy for dealing with glare on the window? I usually try to tuck it behind the window curtain, sometimes even g-taping the curtain in place around it.
1.5L Grey Goose - for the backup power ethanol fuel cell? I find I get more bang for the buck from Stoli, though am constantly frustrated by the inability of the cafe to sell a can of tonic water.
How much record time do you get off the GoPro? Looks like you're just running it off battery, and I'm guessing that if you have the WiFI monitor on all the time that it runs down pretty quick.
Cheers!