mine was like that,looked like its pressed in,i used a slitter(grider)to cut the tube along its lenght.only problem is that you will need a new host.i had a super beast thing host,drilled the heatsink .5mm and it fit just nice.of coarse its after i had tweeked it abit.
Why do you want to take it apart? the IQS 405nm pens are already turned up about as much as they can be as it is from the factory.. at least all mine were. There's no point in trying to 'pot mod' one unless you intend to replace the driver with one that would source more current.. and if your wanting to go to that trouble, just do a PHR build in a small cheap flashlight.
Though they aren't really pressed together. Just glued. But your almost guaranteed to break them if you try to dismantle them unless you cut the host away from the module/driver.