I haven’t pulled out the lens or reflector yet. I’m still resting my fingers. It looks like the standard, orings, lens and very small reflector. The LED will have to be mounted on a very small diameter round.
I’ve been on a 4C binge lately. I don’t know of any place to get a bare 4C LED, so one would have to be reflowed off a 16 or 20mm base onto a smaller one.
Mouser have XM-L2 T5, 4500k in stock. Bare led.
Check my signature.
Currently the XM-L2 datasheet is sorted after bare emitters and kelvin. 
Breakdown pics coming momentarily.
If the bezel is glued get some anti adhesive gunk and apply it carefully. I’ve removed quite a few glued bezels and drivers lately with anti adhesive, and it’s really easy and doesn’t require any force, stress or abuse.
Also what’s the tint like in high mode? If I remember correctly from selfbuilts review it uses a non pwm driver which can cause colour change in an xml in lower modes, but in higher modes it should be at it’s normal colour. The fenix TK75 works like this, in moon mode it’s green.
The things I do for science. I hacked my bezel and o-ring a bit, but, for my Bros at BLF, no problem.
Here is what comes out of the head. The whole set-up is like a little P60.
There is a small groove cut out inside the battery tube to accommodate the little tab on the side.
I'm not even going to mess with the driver. It is tiny, and very propriatory looking, with a unique mounting set-up.
If anyone mods theirs...I want to see. Just curious about who's putting which LED into it. I wonder how an XP-G2 would work with the S20s XM-L reflector.
That doesn’t look like something I’d dare mess with. I guess I’ll just have to learn to live with it, at least until one of our more experienced modders breaks trail…
Actually, swapping out the emitter is just as straight forward as any light. I wouldn’t touch the driver though.
Good one Bort. I liked that.
Wow! You must hate the tint even more than I do!
I swapped the emitter in my S10. I don’t have an S20, but it looks to be of very similar construction. to access the emitter:
(1) use one of those rubber jar opener pads from the grocery store. Put the pad on the palm of your left hand. Hold the light in your right hand while pressing the bezel very firmly against the pad in your left hand. Twist. The bezel should come right off.
(2) With the bezel removed, insert a battery into the battery compartment. Push on the back of the battery. This should push, the lens, reflector and pill right out. The reflector is screwed into the pill.
(3) Use tweezers to remove the plastic isolator / centering device from around the emitter.
(4) The star should now be easily accessible. Replace the emitter with one of your choice.
In my S10, I tried replacing the very greenish XML with a different cool white 6000k XML (looked very green, even though the exact same emitter in a different light at 2.8 amps produced a beautiful pure white beam), neutral white 5000k XML (still didn’t look good due to low current. Everything looked yellowish), a 3000k XML (everything looked orange), a 5000 XPG2 (still yellowish, but more throw), and a Nichia 219 (finally perfect tint… but not very bright).
I think one problem is the Olight just pulls fewer amps than what I’m used to. The later Cree leds tend not to look very nice at low current.
It’s the driver that causes the colour change as it doesn’t use PWM, both a pro and a con. These drivers cause colour change in lower modes, so just about any emitter will produce a coloured tint on low mode. Replacing the emitter may not resolve peoples complaints on the tint, unless as in your example they use a Nichia.
I’m wondering how an XP-G2 would work out. Foursevens lights seem to have gone from green to white since they switched to XP-G2. It’s just matter of how the beam profile would be affected with the XM-L reflector.
Overall I don’t have a real problem with the tint. I mostly use it on high outdoors, or for peering into a dark trailer or car engine. White wall and real life are two different creatures.
I modded my S20 with T6-4C from FastTech. If you have retaining ring plier there is no problem to remove the bezel ring. This is now one of my favorite EDC flashlight.
Is the base 16mm, or did you reflow? I didn’t measure it, but it looked much smaller than 16mm.
The original led base is 14 mm. I used 16 mm without the problem, but then you can’t use the original plastic centering and insulating piece. Insread of the original one, I used this part from fastTech:
Well it just so happens I got a bunch of those from FastTech today, along with some 16mm XM-L T6 4C.
Did T6 4C swap improve the tint issue? Or is it now too yellowish due to being under driven (as reported in one of the previous posts) I was planning on buying the S20 but the green tint issue would be a deal breaker since I usually prefer a NW.
How bad was the greenish tint on the higher modes? (with the original emitter). I read elsewhere an S20 owner stated on the low settings it’s greenish, but on the two higher modes it has a nice white beam without any green. Maybe he was a lottery winner. I also read where an S10 owner had the same complaint and swapped for a T6 3C and now loves it.
I never swapped an emitter before but I have done some soldering on circuit boards (not flashlights) so I’d maybe give it a try if it’s not a total PITA and I knew the results were going to be worth the time and cost of doing it. (I can get the S20 for $39.99) I really like the S20 price and form factor, next choice may be the Sunwayman C20C for $58.00 it’s a comparable size (1mm shorter and 1-2mm thicker) but it’s not available in NW either, and no tail magnet 
Even as sickly green as mine is, I feel it’s a good value. I will try changing emitters as soon as mine arrive, so I’m very interested as well.