With an Osink, most of the annodizing can stay.
You can remove the heatsink later when it outlasts the original magg host.
Undue the switch with the allen head wrench, slide it down a bit, then use a small hammer with chopstick in the switch hole to tap out the heatsink from behind.
Desolder the leads, and your heatsink/emitter assembly is ready for a transplant to a shiny new mag later.
Transistor heatsink compound is what I use, go for it.
This will help the osink slide right into the barrel.