Ok think I follow your idea of what you want accomplished,but my only two cents i can give you of advice is, 1 cent)is there a particular purpose of doing so?because there is certain way to make sd card the main directory, or store certain min cache files but with huge crash risks,but some what possible to do. 2 cent)by why in god's blue heaven would be such a situation bad enough to tamper with system config. files,yeah it's your equalbgiven right to do what you want to your mobile device,but seriously,it's hard to even see where your going with this procedure,so it's definitely not hard to see there would really be no good out come of it,I strongly recommend not tampering with any system config. files without doing a long thorough study on it first,because one small slip up there be no amount of command typing that would sve it then,sorry to look negatively at your idea but the system files are there for a reason,and that's to make your device run. Good health to you and your device & good luck.