Thinking about a Malkoff VLM head plus lamp for my Surefire E1L. My questions are these. Is the stock E1L LED KX1 head one piece or two piece. Does it come appart at the lower ring to remove the lamp? it does not seep to unscrew there. Since this head is dual output and the Malkoff m31's single, can I use my stock Surefire tail cap switch?