mid 2012: Careful of the left speaker (on your right because unit is upside down). Gently remove with spudger tool before removing logic board and when reinstalling press firmly back into place with spudger. Install speaker after putting logic board in place but before installing screws.
Install 2 outside screws first and then single inside screw to allow wiggle room to get outside screws in. Do not tighten screws until all are started.
Use a #1 phillips with a swivel head and press firmly and all screws will come out without issue.
Worked perfectly. As noted below in Landon Mckee's post, at the top of this page, this installation should only be used for a secondary storage drive not your primary or OS drive as the ports they are connected to run at different speeds.