Hi!
Pretty sure this isn't intended (as phased mobs shouldn't give +rep), but if you do the initial Therazane rep quests, don't turn them in!
Instead, start grinding on the mobs around Lorthuna's Gate (59.13 x 40.33 in Deepholm) when you get the first quests for Therazane Rep:
Unsolid Ground - Quest - World of Warcraft
Hatred Runs Deep - Quest - World of Warcraft
Each mob killed gives you around 6-10rep, and it probably works up untill you 35999/36000 hated - I'm doing it now and I'm not sure how much rep does it give as I haven't reached the cap yet.