I applied the modified .BIN and .CL files last night, and my hash rate improved marginally by about 5-10Kh. Haven't had a chance yet to flash the bios, but will try soon.

Interestingly not all of my cards are performing at the same level, GPU0 consistently beats out the rest at an avg 690 now. GPU1 and 2 are around 675 and GPU3 doing the worst at 665.