If leaving card reader attached to top shell this step should be part of step 6.
Also, these screws should be removed in step 5 to prevent breaking the clips that secure the card reader to the top shell.
Some more details here as well.
The newer model without SACD support appears to have added that clip to the back right that needs to be pressed to release the top shell.
If equipped with the card reader you can either have to disconnect the ribbon cable or unclip the reader from the top shell after lifting it up to get finger or tool in there to push clip to side and release reader from top shell. Note: if you failed to remove the card reader screws in the previous step these clips can break.
As mentioned and I’ll add so detail too. If you have a model with the card readers there are two more small screws that also need to be removed before moving on to the next step.