I've had the Hailey 3s in my system for about 4 months and I'm really pleased. They replaced Hailey 2s and I'd describe them as significantly more refined, fuller sound, and way wider sweet spot with great off axis listenability.
Yes, you can replace the faceplate, the tweeter, the crossover and the binding posts in the full upgrade. I believe the Hailey 2 upgrade to version 3 is identical to new production, but you can call YG to verify.