Pacing recommendations - Skull 120

I was hoping someone could point me in the right direction – I am doing the Skull 120 in June https://www.adventureharney.com/ . It’s a long ride (128 miles) with lots of climbing (9,000+’). My goal is to finish. I want to be sure to leave it all out there and do the best I can

What would be the correct pacing strategy up all the climbs throughout the day? I did a 5-hour ride last weekend (5000 feet climbing) and did all the climbs in my sweet spot zone. I was trashed by the end. What do most people do? Keep in in Zone 2? Zone 3?

Thanks so much in advance

stay in z2 as much as possible, if you’re into z3, you better be out of gears.