To open the controller there are 8 screws on the rear that need to be remove to access either side of the controller.

We start with the left side as the battery is this side.

Start by squeezing the indicated area with your thumb

Then twist whilst pressing the squeezed area to open the controller to the left similarly to a book. As shown in the second image

There are 4 connections hold the top piece in as labelled

1. Rumble motor connection

2. Macro Button connection

3. Battery connection

4. Interconnect Flex Cable

Disconnect the battery first before disconnecting anything.

To disconnect the ZIF connector by picking on the grey bale. As shown

In order to remove the PCB, unscrew the two screws as shown

And with that the left side is tore down.

Apply pressure in the region highlighted in the images.

After which twist the controller in the direction shown

There are 3 connections for the right side.

1. Interconnect Flex Cable Connector

2. Rumble Motor Connector

3. Macro button Connector

To disconnect the flex cable follow the same steps as the left side

Remove the screws highlighted in the image

That's the right side torn down.