i just got a new battery today cause the other one had couldnt hold a load. i test my alternator set by starting the truck and disconnecting the main neg. so that why the alternator was running the truck by it die right away. i has a delco si 10 63 amp alt. it is set up the way it is suppose to. terminal 2 is jumped to the battery term. and terminal 1 goes to a dummy light/ fuse and then to the ignition switch, out of the switch and to the battery. so if this is right? how do i tell if the alt. is bad?