Paul! I always admire people who manage to get plumeria to bloom in not exactly tropical climates (where in Indiana by the way?).
I think you want to make sure to enjoy your blooms as long as possible! So that kitchen window sounds good for now. Once the bloom cycle is done I would take them to the basement and let them go dormant. There is a case for spraying them prior to putting them away to make sure you are not storing them with a bunch of bugs attached but I guess you probably do that before taking them inside. Then get them back outside as soon as your night temperatures are reliably over 50 degrees.
I am sure others have suggestions for you as well. I'm lucky that mine can stay outdoors year round....
