Davion, I'm interested in your switch method.  Did you put a switch on the smaller cable going to the positive battery terminal?  I haven't seen anything in the stores to do it easily.
Ideally the switch would be conveniently located in the cab.  Maybe a relay that only uses power when switching.
I disconnect a battery cable on our 2 infrequently used vehicles.  I see battery post disconnects that only fit the negative post but there isn't room for it on the 1992 GM van.  
The problem is compounded in a cold climate because it takes more energy for a start and charging is less efficient so even vehicles used daily for a short run will gradually run down.  Especially if there are several starts in a shopping trip of a few blocks.