Update (08 July, 2016): Copying the modified APK back to Android on an MCTD head unit requires one more step. Modify the file permissions of the modified APK on the head unit to rw-r--r-- (see photo below).
If you endeavor to move the reverse camera display, from the very small window that Subuarus provide to the Android Head Unit (which I covered in my previous post), then you'll soon find that you'll need to adjust the reversing guide overlay. I found specifics of the procedure here. The basics of the procedure are to measure parallel extending lines from the back of you vehicle, mark the distances, then modify the overlay accordingly. Many thanks to my wife who rendered the final overlay (in <15 mins I might add).
Image Descriptions: Android OEM overlay (left), OEM overlay with my drawn overlay superimposed (center), & the resulting final adjusted overlay (right) click the link to download it.