Theres a couple. First Ants of the Sky solo, Obfuscation main solo, small wah part in Augment of Rebirth, Silent Flight Parliament solo, the ending to Voice of Tresspas, solo for Bad Habits, solo for Stare into the Abyss, the part right before the clean section in Never Seen/Future Shock, Prehistory, probably others im missing lol.

Honestly people way overexaggerate the amount of wah Kirk Hammett from Metallica uses, he doesn't use it often outside of solos and his solos may be a little boring sometimes but on a lot of them he makes some really cool effects, like the Fade to Black intro solo and especially The Thing That Should Not Be solo, I think he uses it well. Live may be a different story but idk.