yeah… that will be very interesting.too bad Fenix glued everything :Sp
Nice job there Tom E. Its amazing what a small change can do for the big picture.
I find it a bit surprising that also the more high end manufacturers fail to do the obvious to get the most out of their designs, what would it cost them, a few dollars on a 100+ dollar light?
What? Who wants to buy something that can't be made better? That would take all the fun out of it.
very nice mod tom - i am regretting selling my shocker actually… if you ever want to unload that thing you know ill give it a nice home 
Yes - sounds like LockTite sealed for the TK75, but of course, that hasn't stopped us before. I and others did the Crelant 7G9 ( I scratched mine up some), others (_the_ and a couple others) cracked open the TN31. But the TK75 will have it's limits - smaller reflectors in diameter and depth. It's probably pretty tweaked now, for the XML U2's though - it's an outstanding quality design for it's size.
Where can I buy the AR coated lens that big?
I got mine from Olight… The SR90 lens fits perfectly. Kudos on the upgrade. I had this done a few months ago. I absolutely love it.
When has a light being a great design ever stopped you from making it even better? Lol. With the smaller head I know the same results as the shocker would be impossible but going XM-L2 U2 on sinkpads could very well net 3500 OTF and 125k cd putting right up there with it’s much more expensive brother, the RC40. If you ever get bored or curious. Just sayin’.
What is the MM of the lens? I know a bunch of glass companies that i work with maybe i can get a batch made up!
Agree bout the TK75, it could made better. For the Shocker, If I had unlimited resources and tools/skills, I'd take weight off that reflector, as much as I could by milling/drilling it down, then replace or layer on top of the pill top a copper heat sink, thicker, integrated tight to the surrounding aluminum. Now you got a framework to work with - great reflector, size, and proper heat sinking. Then you need a driver to go 4.5-5A per LED with boost - no auto step down. 3 18650's won't last too long though, so, extend the body to take another 3 batt carrier, and get a side switch on it. That's All, You're Done! 
i like the way you think!
If I remember correctly, about a 95-96mm would be about perfect. The stock one and the SR90 one are both about 93mm. They work ok, but have a fair amount of play.
The 59 mm UCL/p fits both HD2010's and Small sun T08's (got one on each) - I like them, would be better maybe with glass, but flashlightlens doesn't make the big UCL's.
beamshots?
rdrfrtonty can have the pleasure - I'm backed up here...
this is making me regret selling my btu shocker …. but at least it went to dale who did a similar mod haha
Yep, I’ll make sure to do some beamshots when I get it back. Brother and I just got back scoping out new photo target areas. Found a good spot with good potential for 500-600m shots. A long pipeline right-away cut through a national forest. The path is roughly 25-30m wide I think. Want to do the BTU, SR90 (w/ SBT70), TN31mb, TN31 (xml2 dedomed), TN31 XML2 (on copper), and TK75. Will likely throw in a couple more moderate throwers like 7G5, M3C4, & SR51 for comparisons sakes to the serious throwers. We want to do full distance shots of the 500-600m, and then get perhaps 25-50m from the target to show much better how much light actually makes it there. That way we won’t have to worry about zoom screwing up the long distances. Not sure how much light those last three will get to a target that far, perhaps none, but maybe .1L or so.
So is the plan anyway.
Very nice! Looking forward to hearing how it stacks up to your other lights now. 8)