I really want to see Scallops done as maybe being able to do them Sous Vide would get me to make them more.

I’ve done this before in a similar way to what you did and loved it. You have added a few suggestions (type of fat and drying in the refrigerator) that I did not do, but now will have a perfect excuse to use to cook some more very soon!!

Two circulators may work but they may fight each other a little bit. When it gets to temp you may want to shut one off.