Different stars or heatsink sizes

I'm about to mod my first flashlight and i want to make sure that I order the right parts. I'm going to mod a Trustfire TF R2, what size stars will fit? Also what size stars fit P60 and C8 pills? I have been searching but getting conflicting answers. From what I understand all of them use 17 MM drivers.

14mm will fit and generally 16mm will fit as well but that's not always the case.

P60 usually uses 16mm though the newer varieties use 16.5 (the dropins with the really BIG holes for the wires)
Depending by the dropin LED heatsink/star, HEIGHT may be of essense. i.e. the 10mm cutter ones are thin and some dropins will not let the reflector screw down enough.
Another issue is where the soldering points for the wires are on the star. If you have a look at the bottom of the XMl & XPG reflectors you will see a ring that goes around the LED. You do not need any wiring there, so a 14mm may not work (I have never seen a P60 with 14mm star size)

Now the C8 is 16mm but i have seen some with 20mm stars....

Open it up, measure what is in it already, and go from there.

Thats what i will do I was only asking because I'm deployed to Afghanistan right now so this is what I'm trying to do on my spare time. Shipping takes a while here so I was trying to order everything at once.

Thanks, thats some good information. So, I got some drivers and spare amc7135 chips in the mail. Wow they are a lot smaller than they look in the pictures. Time to order a magnifying glass