How long has your gallbladder been out? I ask bc mine was removed about 15 years ago, and while my digestive system was weird for a couple of years after, it has . normalized since. 16 or even 18-hour fasts are no issue. 24-hour fasts do involve a little wobbliness, but that seems to be true for most people, with or without gallbladder. I realize that does you minimal good now, but you should know that this may not be forever.
For now, I think the suggestion to stop eating 2-3 hours before bed, then to skip breakfast, will get you into a good zone. Also, where possible, break your fast first with a small, protein-rich snack—have a big meal only after that.