Probably will need to try both 2f and 3f to see which shoots best in your gun. 4f in pan for priming. When priming you want just enough powder to catch spark, you don' t want to cover up touch hole, the idea is that the fire flashes across top of priming powder and sparks fly thru touch hole. Also after each shot wipe frizzen, pan and flint with cloth to remove residue makes things work better. And polishing pan is a good idea. Any other questions, always glad to help fellow black powder shooter.
David/Mo