Quoted from Aniraf:Ok. Let me clear up the confusion. The last picture is an entirely new core, the first picture is the original mushroomed out core. I cannot remove the mushroom core without damaging the magnet. Unless I can shave off the mushroom like captainneo suggested.
I had the same problem with my highwire lock magnet. I took a simple rasp (that is smooth on at least one side), placed it flat on the top of the magnet (smooth side flat on the magnet, rough side facing towards the core) and ground off just the "overhang" all around the core that is blocking the magnet. Took less than a minute. You don't need to shave off the complete top of the core, just the little rim around the core.
The metal is very soft, it comes off easily when hit with a rasp.