Hello,
I built my system: Z77X-UD5H Mobo, F7 BIOS, Core i5 3570K, 8GB of Kingston HyperX, and a Radeon 6870.
What i did, was clone a Brand New Mountain Lion partition from my iMac, onto my boot disk; and then boot into it using the Unibeast menu; as i wasnt having much luck installing...