I think you'd get a lot more people coming to it if the thread was named for what it actually is. Currently, the threads title is "DIY Guide for Extended Battery" Not what it should be: "DIY Guide for Extended Battery Case."
Adding to that, it's nothing that you need to be concerned about pertaining to difficulty. If you're scared of using an exacto knife, then use a dremmel. If rotary tools aren't your thing, you can also use a butter knife, and heat it up with a lighter, or torch, or on the stove, and slowly melt-cut your way through the case.
There are numerous ways to perform the same type of action, it just depends on what you are willing to do.
I'm going to do this next week, and post the results, and a video while I do it, showing just how easy it is to accomplish, and perhaps that will get more people doing it.
After all, this is currently the only way to get one.
Or, I can go into a small business venture, and make them for people then charge a slight bit extra for the work. I have a dremmel, and several other fabrication tools like plastic files, and shapers to round off edges, so I can make it look and feel a lot more "natural" than the "standard person."
@Akikhia when I post the video of me doing it, you're more than welcome to put it into the main post of the thread.