To completely isolate the second battery I put under the back seat, is
disconnecting  the (-) cable sufficient or should I disconnect both (+) and
(-)?  Both batteries are tied together right now.  The "second" battery is
actually the one I want to save for starting purposes since it has the
heavier cables going directly to the starter.  (The original battery is
still in place with all the factory wiring intact.)  One of these lever
style disconnects would work very nicely for this.

                                                   Jay  '85 Westy (The
Hindenburg)