I would personally move Gerald or whatever snake is in the smaller cage. I dont think stuffing Phyllis in a T8 is going to do anything but make her push more. When i put Caesar in my 'cleaning T8' that i use for the active snakes when i dont have time to watch them and clean the cage, Caesar really isnt happy about it and after about 10 mins of looking around, he starts pushing on the doors to get out for pretty much the full 30 mins it takes to clean his cage.
Imo, not the best idea.