Drives, vintage, Fretters, and others...
Thanks to soaking in ATF and acetone for a while, and then heating with a heat gun and spraying with Seafoam Creep, I just succeeded in removing the tail piece from my frozen solid bullet vise.
Here is what I did to get it loose after the penetrating oils did their work...
1. To see what you are doing, using a wire wheel, remove paint from the joint between the tail piece and the main casting.
2. Find an old blade from a utility knife. Tap it into the joint using a small hammer. (Be careful, it's sharp).
3. Work your way around the tail of the vise wedging the joint open a little bit at a time. Graduate to wiggling a piece of sheet metal and then tapping a cold chisel after getting it open a bit.
4. Keep at it moving around 360 degrees until it drops off.