the devices are practically the same, except from the radio...
and the EScreen on 9900 include items only applicable to 9930...
so perhaps it is only the radio files that needs replacement?
would be interesting in trying though...
Don't try it because even in a remote case that you were able to load the OS, it will brick your phone for good. Not only the radio file, but also several other .cod files are different.
Wait for a leaked version, or a hybrid which may be available. In either case, make sure that your data is backed up, in case you have to do a hard reset.