Attention ***** it has been discovered that this conversion engine will not work in the very first run (of 16 light) of Mac's EDC lights.
The very first run of 16 used a shorter reflector, and a shorter head
You can identify the early first run heads by their length (36mm) or by the fact that if you put in a completed conversion pill, the light won't screw together.
Later runs had 39.4mm long heads.