HDD does not actually need to be removed to replace the fan (Steps 3-6) and can stay where it is.

Steps 17-20 can be completed much easier by removing the keyboard first.

Remove the plastic trim across the top of the keyboard.

Remove the 4 screws the trim covers.

Lift the keyboard carefully from the top, there are only tabs holding the bottom of the keyboards which the keyboard slides out from.

This makes it easy to get to the 4 cables shown in steps 17-20 for removal and reinstallation.

I will edit the guide once I've sorted the photos later today.