If you don't need the ring generator for the common bell than I'd go with #2. You can't send the ring voltage down tip and ring when you're using the talk battery, of that I'm pretty sure. If I'm wrong about that someone will correct me, I do think you'd blow a fuse before you ever hurt the filtered battery though. Been a long time since I use 105 volts out of a tone commander so I really don't remember, the wiring scheme is on the side so that should help you.
