I run a 60GB SSD drive as my "C:" drive, with my OS and MB drivers on it. I want to run everything else off my legacy 250GB HD--------------but it seems the install disc for Diablo III only wants to use the "C:" drive for install----------is there a workaround??--since my "C:" drive does NOT have the requisite 12Gb available space?

System - AMD Athlon II x4-631 CPU, 16Gb Ram, AMD 6790 GPU, on an ASRock A55 Pro3 MB

HD's - OS and system drivers 60Gb SSD; 250GB Seagate HD