I found it best to start by removing the keys starting at the bottom left

The first 3 square keys on the bottom will be the hardest to remove. Once you remove them, access to the others will be easier.

To access them you must insert the modified tool in the gap between the key and the aluminum case.

You then must get the tip of the tool above the key tabs and the key scissor clips that hold it on.

The clips that hold the key are circled in orange. Pull the key back in the direction of the red arrows and slide the key off those back guide tabs. Please look at the next step for video examples of how to remove the keys BEFORE trying to remove them.