I only have 2 snakes atm and they are on hoppers. I doubt this would work for large scale feedings, but...I put one f/t in an individual ziploc bag and let it thaw to room temp during cooler weather/thaw in fridge if summer, etc.
Once thawed I place the ziploc bag bottom with the f/t in a small but deep plastic container filled with warm water and use something to hold it submerged (silverwear piece is what I use). Depending on whether I thawed it at room temp or in the fridge I will refill the warm water 2-3 times to make sure it's as much of a warm temp as possible for the snake w/o worrying about it being too hot.