With help from a user here, I was able to finally achieve an installation of Mountain Lion 10.8.4 on my Late 2007 MacBook 13" White. I followed their instructions which happened to be the same as the instructions within MLPostFactor V. 0.3 and even followed along a YouTube video because it did not work the first time. It worked perfectly this time, however, as per the instructions of creating two partitions on an external hard drive—(1.) Install and (2.) ML— it booted perfectly into ML only with that drive connected, and holding Option for Boot Mode then selecting the ML partition. Makes sense. I don't want to go through this process every time I use my computer. If I disconnect the external drive and restart, it goes right into Lion with all my files still there, like it never went away. How can I do a clean install of Mountain Lion on one partition (my main drive)? I only want one main drive for all of my computer needs. I don't need Lion anymore, and I don't want to have to switch between the two. I read it was recommended to install it via external drive this way. Did I miss the last step or is that it? I need to use an external drive to use ML? Thanks for any responses, I'm not familiar with these processes.