Sounds interessting. I was frightened to "crack" it open, had the fear to destroy it totally. But i will give it a try (again).
Maybe there is a chance to extract the partition from the official firmware .zip? Maybe using "dd" under linux? I will try it when i find time the next days.
I am using a Sony PRS-T1 now, but my wife would like to use the 360 because of its beautiful cover