it's similar to the skit files (as these are scs files too). you have to find the difference between the us and jp files then manually add the missing pages and texts. scsedit don't handles the end-of-text character correctly so it needed a bit of hex editing too. for some reason, when i tried to fix scsedit there were weird problems like randomly unloading pages and such.
anyway, i'll post the already packed zhonecage cpk with the guide, which will be done soon.
in the next guide, i'd like to add size checking to detect already repacked files. just to be sure, these sizes for the original files are correct for everyone, right?