Title pretty much sums it up. I have a M600 DF on my MK18, and I would like to shorten it up a bit. The Surefire body would go on my 16" midlength and eventually receive an OKW head
Yes, it will work.
ETA:
If you don’t already have the Modlite body you might want to consider the Reptilia Torch
Looks nice, but I’ve already got an Arisaka 1913 mount, and my 16" has a KMR.
You will not be disappointed with an OKW head. I have one on all my main use rifles.
I love my Reptilia torch body. Super lightweight and helps keep the rifle balanced.
I just picked up a few PLHv2 heads for rifle and handheld. In my opinion it has the perfect amount of throw and spill for what I use it for at work.