Mercedes-Benz S320 Forum : “battery automatic charger and fuel pump”

Why not just buy a quick disconnect for the battery post?  When it's in storage disconnect so there's no draw.  Course that would mean recoding the stereo every time.. hmmnnnn...  Maybe this is the answer:  http://www.summitracing.com/parts/ATM-9201/       The fuel pump I would go to Mercedes for and not mess around with aftermarket.