One more photo posted in the bottom of the OP. Painted.
Hotrod Fugu (河豚 or 鰒; フグ)! Me like!
That’s wild!
Showing my age here but if DG made barrels like their air cooled heads then I guess it would of looked like the heatsink here. Its certainly one different looking light. 
08/25/15 - The light is finished. Photos in the bottom of the OP. I claim the duck as the winner, in our little contest. He took the long road and is making a beautiful custom light. I took the quick road and made, well..., something bright.
You win the “finished first” badge, I still hope to win the “finished at all” badge. Hey, these days everyone gets a prize, right?
Looks great and should provide some much needed cooling for that emitter.
My oh my will that burn people’s faces off!
Lol…looks like a laser weapon from an old sci-fi movie. Cool! (or should I say Hot?) 
I can’t quite make out how you joined the two body tubes together? On my 502b the threads at either end have different diameters.
Bore the ID of one and remove some of the OD of the other, to where they are a press fit. dremel tool or drill press.
Words fail me. Are the ducks (pun intended) on the pond scared of this creation in and out of the water?
I’m more concerned about finishing than winning. I do think this was a good idea just to see how different two builds starting from the same host can be. I’d like to see more build offs like this.
https://budgetlightforum.com/t/-/34467#comment-782951
A couple of beam shots. All flood, but nice and bright.
Looks like a winner.
Looks good, but why did the word “EXTERMINATE” come to mind when I first looked at it 
That will dig the fans out.
Cheers David
I knew it reminded me of something….
another great custom light by OL. love the tints of the new XHP emitters.