Excellent guide. I'd add a couple comments of my own.
If you're replacing the hard drive, you can stop after step 11. As others have noted, there is no need to disconnect the wireless antenna. Carefully move the antenna plate off to the side, cable connected. You'll have plenty of room to access the drive(s).
1. If you're replacing the OEM drive with an SSD, you can safely leave off the plastic. SSDs are in a plastic case and don't have an exposed circuit board. Omitting the plastic will not affect the wireless antenna.
2. After replacing the antenna plate, if may be a challenge to put the two 6.6 mm T8 Torx screws in if the drive isn't sitting in exactly the same position as the old one. If it's off by even a smidge, the screws will be difficult or impossible to put them back. Don't worry. If the drive isn't flopping around, you're OK.
3. Note that the fan cable is correctly oriented when reattaching it. I had it black side up. Wrong. The gold contacts face up when reattaching the cable.
