Thanks,
I used a small bench grinder to remove the lug. You could use a dremel tool or even a file. The Al is pretty soft so any method won't be too hard. With a file you might have to finish up with some emory cloth as you might not be able to file down really flat. If you wanted to remove the magnet you could put it inside of some type of rubber boot that would slide on and off that end of the light.
A Chapstick cap works, I'll be using that until I can figure something better.