The NBI app will sometimes give you the options before you install but I think it is stuck into the mode (in the NBI app include in the path) where it believes you have previously installed Chameleon and won't ask for any options.
I am glad to hear that one more S10-3 user was able to boot into OSX. Thanks for the feedback -- I have edited my original post. I just hope you will use OSX for good and not evil.
Extra is a truly hidden directory on purpose though it will appear in searches if you look for "Extensions" or any other file or directory it contains. I didn't include anything about it because I didn't mess with it with the install method I used.