53 chevy half ton rewired the truck last summer. Battery will go dead if it sits for 2 days. Battery was tested, new alternator,one wire. Is there there a tester I can use to find any open circuits when the truck is shut down?

https://sites.google.com/site/bluejaygarage/home
53 half ton http://s159.photobucket.com/user/sworden73/library/?sort=3&start=all&page=1
72 Nova SS sold
75 Corvette
52 Chevy Styleline Coupe