Amplifier Box (Small 12v Amp)

EDIT: 4/28/16 FINAL Change I hope, Added glass fuse couldn't find a panel mounted fuse I liked for a blade (couldn't find one locally either) so I bought one from RadioShack. I also added a strain relief with a lock so wires cant be pulled out. Widened the case some to give more room. Stereo in stereo out dual phono/rca plugs. There will be a couple different versions in the future. Changes like with pot and fuse or without pot with fuse etc.

As the title states, a box for a small amplifier. I put in a Pioneer AVIC 5100NEX in my 04 Ram, along with headrest monitors for my 4 year old. Once the install was complete I had no sound out of the headrest monitors, or so I thought. Engine off volume down low, I can faintly hear the volume from the headrest monitor or headphones. It appears my head unit puts out a certain volume and its up to the headrest to have an amplifier to well amplify it. Apparently the ones I chose are cheap and don't have it, so I purchased this amplifier from my