I'm planning to do it, the equipment is already on its way to me, the only difference being that mine is a 4D Maglite, but voltages remain the same. I intend to put a 1 ohm resistor on it, which should limit current to 1158mA, including the internal resistance of the batteries and other components (switch, housing, etc.)
You Could allways put one of the many regulator circuits in the thing. It would work fine and you could get a nice flat output over the entire runtime(unlike direct drive).
I am quite partial to regulated reflectored lights.
Absolutly the way to go.
Yaesumofo
6V to a single L3 is going to be quite wasteful when using a resistor or linear regulator. With a 1 ohm resistor, I'll bet you'll get more than 1.1A of current. Your best bet would be a downboy converter, which would ease the load of the batteries (for 1A, a DB1000 would be around 80% efficient, and would reduce the current load on the batteries to 760mA), and provide flat regulated output.
I did a 4D and it had crazy runtime compared to my 3C but I don't remember the exact over all run time and the current I set it at was less than I prefer.