Here are the instructions to replace the usb charging port on a 2013 Nexus 7 tablet. The parts are different on a 2012 version, so don’t use these instructions for that model. (replacement charging port part links at the bottom of this post)
Although the parts are small, and it takes a little bit of time to complete, you can replace the digitizer and screen assembly for your Nexus 7 without much trouble. To begin, you will need to be sure you ordered the correct screen assembly.