Sure would if you can adapt it to the 20mm mounting space.
-Garry
Omg thanks sooooooo much, fonzeka!!
Amazingly my light came alive when I thought it’s gone! Without the reflector the light became a very nice uniform flooder. Then I slowly place back the reflector, and the lens, then lens cap and screw it less tightly. Now it works like before! Really didn’t expect the fix to be so simple. I’ll wait till tomorrow and try again and see if it still works!
And to all others, thank you very much for your prompt assistance! I got my HD2010 ‘back’! Totally made my day.
Ok, well you need to place some sort of insulator between the reflector and the LED (find some thin plastic and cut into a "donut" shape to go around the emitter).
-Garry
Garry, is this a common problem for this flashlight?
Yes, but my HD2010 died immediately after I created an insulator! Really @$%ed me off! I was so careful to hardly use the light before I got an insulator in place and it died anyway!
-Garry
I’m glad it worked out for you radiancez567 
I used some thin electrical tape on bottom of my reflector to prevent it from shorting.
Garry the HD2010 driver is 17mm, check the review UPDATE: 5/19!! Review: ULTRAFIRE HD2010 from Tmart (warning: lots of pics!!)
Ah! Ok! I knew people were doing the P60 pill method of putting in drivers and couldn't remember why (thought it was due to a 20mm mount space). Now I remember it was due to not being able to solder to the aluminum pill.
-Garry
Good News radiancez567! Yep, that's a common problem. I got a stock supply of the insulator rings (plastic, glued back, etc.).
You mean the insulator caused it to die?
I’m very glad indeed. Time to look for a tape!
Thanks for the good news
No, but I'm not sure why it died. I used a piece of thick packing tape, but maybe I shorted through it.
-Garry
If you were planning on stacking extra chips on the driver anyway, just go with the Nanjg 101-AK. Same programming and chips as the 105C except all components are on the topside and it has a flat base like the original East-092 used in the HD2010. Only has 4 chips (1.4A) but I've stacked onto each for 2.8A in the past and there is no reason you can't add even more. Retaining ring will thread right on and you don't have to booger up the stock pill by modding it.
FastTech has the 101-AK for $2.89.
No problem, it’s still interesting …
What is the max A for a xm-l t6
Not sure. Where did u see that? There's 1A, which is a tint - cool white. Unless someone meant "max amps", if so, CREE rates max amps at 3.0A for the XM-L's, but we like higher 
! Some feel going over 3.5A is not worth it. I'll go to 3.8A if I feel the pill and adjoining flashlight body can handle the heat, sometimes higher, but always with a U2 or U3. My HD2010 is at 4 amps - no problem, but I beefed up the pill and there's so much mass with this flashlight. And I "think" the U3's can handle higher amps better than a T6, so I went with a U3 1C - should be little more lumens as well.
Definitely for the HD2010, at least 3.8A. Still want to mod mine up though -waiting for copper stars from Nitro, then got an XM-L2 U2 to go on the copper, then in the HD2010 -- can't easily do much more than that (well - also have a UCL lens in it 
).
It’s a question I asked 
Sorry for my bad english
So if I put a driver with 10*7135 at 350mA, I should have 3.5a
I should have better performance than the original driver and have better protect of my LED
Oh - so you were asking for max amps? Like I was saying, there are different opinions, different options. That I-O driver linked by fonzeka seems almost perfect - it's got a clean back-side, basically 17mm so should fit stock, it says 4A but guys measured 3.8A max, it's got some crazy programmable mode setting UI, or you could go with the 101-AK driver JohnnyMac recommended and add lots of 7135's, going triple decker (I used that driver before up to 2.8A), add 6 7135's: 3.5A, 7: 3.85A, 8: 4.2A, and it's got a nice 3 mode option.
Well ... Here's where it gets dicey. The HD2010 is considered direct drive, better quality battery at full charge, more amps. With my stock HD2010 and Panasonic 18650 2900, I was getting 4.6A. So using a regulated 4.0A driver, I'm actually putting in less amps, but the light will maintain the higher power better and not be so dependent on the battery type and it's charge state. But now, I can safely use a quality 26650 and not worry about things melting (with a King Kong 26650 I got as high as 5.8A).
Don't be surprised -- there's no "wow" effect when updating this light to a regulated driver, as there are with other lights that are under-driven.
But between 18650 and 26650, will I see a big difference ?
Not with a true regulated driver, just longer run times because of the higher capacity of the 26650's. With some lights/drivers, it does make a difference.