It's great he loves his wet.
I would ditch his crunchies completely. Even if he is only getting a few it can have a big impact on their BG. They will be HC, possibly very HC
You will need to be careful he doesn't get into his sisters crunchies, they will be High in carb too.
We have a multiple cat household and when George gets into the other cats crunchies it really makes a big difference to his BG. It doesn't happen often here, the other cats only get crunchies when we are going on vacation (the cattery won't feed them wet), so it's often in that phase when I transition one to another that he can get into the contraband.
It's nice to see something other than black.