What worked best for me:
1. FL Resize in .308Win die without expander ball.
2. Lightly Anneal neck (too much and the neck will collapse during neck down, if in doubt skip this step but you may lose a couple more cases due to workhardening)
3. Resize in 6.5mm die with the die setup with zero headspace (bolt closes with slight resistance on sized case) from the false shoulder created.
4. Light neck turn
5. Anneal
6. Done
Have about a 0.5% loss rate doing it this way, using used .308Win brass. Just make sure when you're FL resizing the first time the die is screwed ALL the way down to eliminate the casehead expansion (so the brass will chamber smoothly in the new chamber). Don't worry about the headspace, the correct headspace will be set by neck down process.