The tweeter is pretty much just a magnet with two wires, but there is a voice coil embedded in the magnet along with a dome-shaped cone. The wires should connect to the voice coil.

On the newer tweeters the face plate also carries the cone and voice coil so if you take out the wrong screws you will end up just holding the magnet. I've done that a couple of times by mistake...

M60ti, VP180, QS8, M2ti, EP500, PC-Plus 20-39
M5HP, M40ti, Sierra-1
LFR1100 active, ADA1500-4 and -8