Well im not up on the wii and its file formats, the pkg format is just an arcive format used to package multiple files togather like an rar file for a pc tho some what differant. As for the correct couse of action to take, turning a retial ps3 console in to a dev one would be just as hard as getting the keys for a retail and not do verry mutch good at the moment as you can only run dev sigend code on it and the hypervisor limits still apply.
Im not real sure what the right corsue of action would be to take, if a method to run unsigned coe were to be found this would be a great help as then we could probly dump the kernal and keys to make code run on a retail console but all attemps to find sucth a method have faild. And all the firmware upadtes for the console are .pup files witch also are signed and can not be alterd. There are some pkg files in an update file but what they contain is a mystery as they are encrypted as is most of the important data for the system is.