Trouble w/ Diamond Hex tweeter

Being a relative novice when it comes to installing a pair of component speakers, I'm going to swallow my pride and ask you guys for some help. The Diamond Hex tweeter I am trying to install (s600a comp's) came preinstalled in the factory flush-mount "cup" that came with the set, but I need to swap it out into the other "angular" cup that came with the speakers. However, I cannot simply pop the tweeter out, it seems tightly snapped into place and I'm afraid of damaging the tweeter itself if I force it too much. I know, judging from the sizes, that the extra cups will accomodate the tweeter and from the diagram included in the directions, that the tweeter can be used in ANY of the cups included. Has anyone installed a set of Hex tweeters and know what I'm talking about? I just want to know that I'm on the right track. There are 3 small holes on the back of the tweeter cup, which will be used to thread a screw, spring clip, etc. once the tweeter is removed, so I'm hoping this is an easy thing to do. Thanks for the help!!!

The tweeters pop out of the cup. I had to do a little prying through the holes in the back. They fit in there pretty tight.