The clutch was a good idea. For piece of mind, during the tune and for the whopping it will take after the tune. Well played.
For real, I hope it goes well. You are on the right track with building the car up properly I think. Once its tuned, leave it alone for a while and just drive the balls off it. At that point it will be more car than 70% of the members here could handle… so just focus on keeping it clean, safe and driving it like a boss.