Check this one out. Since it has the glass / LCD / housing the repair is super easy, same process as the G4 by the looks of it. It's amazing how similar the insides of the G3 and G4 look...

http://www.amazon.com/LCD-Display-Digitizer-Full-Assembly/dp/B00OPWFM02/ref=sr_1_4?s=wireless&ie=UTF8&qid=1443629510&sr=1-4&keywords=LG+G3+SCREEN+REPLACEMENT