Hi there!
Which feedings were you planning to tackle first...night wakings, the bedtime feed, or both at once? Regardless, if you don't already have a solid bedtime routine in place, now's the time to get one. Make sure there are other activities besides nursing to help cue her that it's time for bed. Yes, she'll likely still notice the change when your wife doesn't nurse her, but it may help smooth the transition if there are other things you do instead, like read a story or sing some songs.
Does she go into the crib awake and put herself to sleep now, or does she fall asleep on the breast? Either way, she'll probably not be pleased at the new way of doing things. When you finish the bedtime routine, and you tell her goodnight and put her in the crib, she'll probably cry. Maybe a lot. She's old enough that verbal reassurance may help calm her...try using a short key phrase over and over, like "night night, Matylda. Daddy loves you." If that doesn't settle her, and she's standing up, do PD. If at any time she calms down, even if she's still standing, leave the room. If she starts back up again, come in, settle her, and leave once she's calm. If you think staying in the room might be better, you can go that route instead, just beware that some toddlers think it's playtime when you're still there. Also, keep in mind that you want to try and do ONLY as much as it takes to calm her down so that new bad habits don't replace the old ones, if you can help it. You'd do basically the same thing for the night wakings. The important thing is that you stay consistent and don't give in. It will be hard, and you might have a few sleepless nights, but
If you have Tracy's new book, The Baby Whisperer Solves all Your Problems, she describes several scenarios for weaning toddlers. That might give you some more tips. I hope that helped somewhat, let me know if you need some more help! Good luck!