Thanks for the feedback!
I never done anything like this before, so to be clear:
I need a 14 or 16 gauge wire (once the tail cap is removed) to complete the circuit, by connecting the negative side of the battery carrier directly to the aluminum body of the light? Am I connecting it to the inside or outside of the body? If the switch is the problem, what options do I have? Can it be repaired by someone who knows what they are doing?