I don't think you can take the head apart. But don't sweat it... the new LED heads fit the older E series incan's. I upgraded my E1Outdoorsman, and now it's been on the same battery for about 6 months. MUCH better than every few weeks.
This is for personal defense and duty use, not needing another high priced toy. I just need a simple light with extreme reliability.
I've not been on CPF often because it seems there is not much discussion about a light that does not involve modding it to hell and back where some of us just need a light to work without issues.
odd that you ask about modding a light but you don't come to CPF often because you not interested in modding a light. maybe you could try a search on self defense flashlights for more insight?
There isn't a drop-in for the stock, sealed SF LED module.
That said, you can get an adapter to fit a SF C/G/P/Z head to an E series body, allowing you to power an M30 or M60.
Supreme Co from Taiwan makes on - I've never done business with them, although they do respond to emails. The last time I looked, their shopping cart was down.
Also, TNC Products makes an E2C adapter - at last report, they were expecting some more in around this time.
Check out the SF "Lego" thread for more ideas.
-Trevor
Justin... are you using one or two cells to power your KL4 EDC?
Do you know if the KL4 head can handle the current from two rechargeables? Considering running one with two AW RCR123A's = potentially 8.4v combined.