I read this thread and tried to install ML on my EX495 and wanted to share my experience so that others can use it. I tried 3 times before I got it to work. I have an out of the box EX495, i.e. without any modifications and three 1.5TB drives. Two main points seemed to make my installation attempts fail 1) Advanced Formatting of the hard drives and 2) using a hard drive that is larger than 1TB to boot the hackintosh.
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I hope this will help others and thanks to all who posted to this thread as it helped me solve this puzzle after reading it over and over. Hence I thought I'd share my learnings to save them some time.
Cheers