My one disastrous attempt at requeening went something like this. I couldn't find the old queen so made an emergency dash to town to find out what to do. I was advised to put a couple of brood frames in the second super, with the new queen, and leave the old queen in the bottom box. Leave the excluder between them and put a sheet of newspaper over it with a couple of slits in it. The bees eat through it slowly while getting the smell of the new queen apparently, and some stay with her. In 3 weeks I was told to separate them, which I did a few days ago. The downside is that the hive which needed requeening was weakened a bit. I still see italians in the new hive. The queen is a carniolan so I keep looking for little black bees, but I'm not certain I'm seeing any yet. The numbers are still low.
I wonder if I'll ever find a moving needle in a moving haystack :-D
All the best with your experiments, hardtime, and have fun trying it out.
Lone