There are four screws in the back of this device. After unscrewing them, the front panel can be easily removed. (There is one clip in each side).
The serial is in the front side, so if you just want it, it is enough.
It is harder to remove the back case because the wiring to the antennas and the power plug.
Front side PCB:
→ port.serial general information about the serial port, serial port cable, etc.
Connect only GND, RX and TX, don't connect VCC (3v3)