DO NOT ATTEMPT TO COMPLETELY SEPARATE THE TWO HALVES AS THEY ARE CONNECTED VIA THE SYSTEM SWITCH DIAL ON THE UPPER SHELL AND THE MAIN PCB.

The cables have been glued down at the connection points as well. The upper shell and PCB unit don't need to be completely separated in order to get in and repair the system although it would make it easier.

Unless you are confident in removing this glue without causing damage and your soldering skills I don't advise trying to separate the two.