This guide is for hinge type K01. This hinge type is found on the following models:
Some colors in the pictures may differ for your model. That is fine, what matters most is the shape of the hinge piece.
The plastic hinge mechanism must be oriented as shown for it to fit onto the metal keyboard hooks without breaking. Notice the hole on the left side of the hinge is narrower than the hole on the right side.
Hook the left side of the hinge over the left metal hook on the base of the keyboard. This works best at about a 45 degree angle.
“Stretch” the hinge over the right metal hook on the keyboard base. The hinge can actually slide apart slightly, which allows it to fit over both metal tabs on the keyboard base. Once it is sitting in place as shown, it will be easier to put the key on if you “compact” the hinge back together. That is, push the right-side underneath portion of the hinge towards the left. The hinge should now fit snugly in its place.
Align the key on top of its place on the keyboard, and press down evenly. All four corners of the key should click into place.