The top curved part of the antenna plate has a thin lip on the bottom edge, but is very flexible. During reassembly when sliding the antenna plate back into position, if the 4 holes do not exactly line up, then try bending that lip downward a bit and the antenna plate should then line up perfectly.

Instructions worked perfectly. Second successful iFixit repair or upgrade in 3 days (first iMac, now iPhone). Fast shipping too for parts. Thanks!

This was very easy to follow. The number of steps seem high, but half are just removing the display to make sure you are very careful with the fragile glass, so there are really only about 35 steps. You may also need to remove the right speaker before disconnecting the 4 AirPort/Bluetooth antennae, currently before step 50. The speaker is shown in earlier pics, then "disappears."