Sorry Dromesburg, for necro-ing an old thread... but I was hoping I may provide some helpful information if you are still struggling with this, or possibly get feedback from you if you have found a solution.
I too have a P6T Deluxe V2, and although I do not have a drive over 1.5TB, I have having compatibility issues with the outdated OROM and my new SSD. I haven't found a newer Asus ROM, nor a compatible substitute, but I have been working on swapping out the old version 8 OROM with newer ones in hopes that they may function. If I find a solution, I will keep you in mind.