you can disconnect it from the crt, not sure about the board

there's a pair of pincers in that suction cup that keep it in place, feel around the rubber, you should be able to figure out its orientation, now squeeze that area and it should pop out

you could use tools, but beware, its easy to rip that rubber suction cup and if you wanted to reuse it (which i assume you don't by your post) it would be dangerous, but more importantly if there is still a charge in there it might make you shout a couple hell worthy words