As noted in comment section under 'Guide' and this step, attaching the new ribbon cable to the ringer switch and volume up and down, is a major challenge. I had the same experience punching out the 3 plastic studs. When I resembled the ringer switch (to go to vibrate only) and the + volume didn't function. Rather than using the same metal brackets and a new cable I searched eBay and found you can get the cable and the brackets (including the metal bracket holding the power) already assembled. Just search eBay for "Flex Cable Metal Bracket Assembly iPhone 5" and there are a couple of sellers in the US and China that sell these; and they are only a few dollars more than just the cable. Then you don't have a problem with this tricky part of the guide. Ifixit should inventory Flex Cable Metal Bracket Assemblies too.