Just finished installing in my 2013. Everything appears to work great. I can confirm that the blue guide lines are not available when you force the front camera, but they do return when you meet all the original requirements for it to enable.
I did not use the other wires labeled input # and output #. I connected the two for the front camera per the instructions and the plug and play cables. The USB I ran down to behind the panel that you removed in the passenger footwell incase it is needed later.
The provided instructions for removing the dash are not helpful. Look for Noah's video in this thread instead. The only trouble I had was trying to remove the wires for the sport trac button on the top of the dash. I broke the tab trying to pull it out and never got it to release. What I ended up doing instead was leaving it connected and swinging that whole dash piece up on top of the dash, and it was up and out of the way.