I love my 2016 XT, but I believe the car has more of a blind spot in the back corners than my 2010 had.
There is a camera back there, but by default it only works when you're backing up.
Some new cars, like the Tesla Model X have the option to run the rear camera all the time on the screen. Sure my car doesn't have a high-definition camera and a 17" screen (or go zero to sixty in 3.8 seconds), but damnit I can have the always-on camera feature.
All it takes is some knowledge, a switch, and a few wires. This project is easy if you know some basic wiring.
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First off the knowledge. Through techinfo.subaru.com I got the wiring for the rear camera and headunit. The above pinouts are not complete, I just filled in info as I found it in the manual. Your car wiring may vary! I double checked everything using a voltmeter before doing any modifications.
I even think I found an error in the manual, as it said that Pin 4 was the +12V reverse on XT's and 6 on Non-XT's. The truth is that Pin 4 is for the Fog lights, and Pin 6 is the +12V reverse.
The head unit is programmed in such a way that anytime a +12V reverse signal is detected, it switches to the camera image. I found it will even display the rear camera over the StarLink Boot screen.
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By back tracing the signals in the tech manual, I determined that there are two places I can do this modification: Behind the headunit, or behind the dash.
I already know that removing the headunit is a major pain, I have done it twice and don't want to do it again if I can.
Connectors i5 and i230 look to be located near the fusebox in the image, so I am targeting them.
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Here is the schematic, spliced together from bits of the tech manual. I will cut the +12V reverse signal just after it exists connector i230, then splice in a switch. The switch will toggle to +12V Accessory, tricking the head-unit into thinking the car is in reverse. I selected the same +12V ACC which is already going to the head unit, just to be safe.
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I removed the trim which covers the fuse panel. And what do you know! Connectors i5 and i230 are right there. Easy access. :grin2:
I confirmed their identity by looking at the pin colors and comparing them to the table I built. I then double checked the pins I am going to access using a multimeter.
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Before removing the connectors, I disconnected the negative terminal on the car battery.
I removed i5, and then removed pin 17 (Yellow with Red). I soldered a second wire to the metal pin, and then re-inserted it into the housing. This is my +12V ACC signal.
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I removed i230, and then removed Pin 6 (Brown with Yellow). I cut this wire a few inches down to split it. I soldered a new wire onto each end to go to my switch. I applied heat-shrink to each connection and reassembled the connector.
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Next I removed the panel which has the dimmer switch.
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I used a stepper bit to drill a hole for my switch.
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I installed the switch and then tested and re-assembled everything.
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The end result is I now have a toggle switch which activates the rear-camera image any time I need it.
When the switch is "OFF", the camera operates like normal: turning on while in reverse and off in all other gears.
When I toggle the switch to "ON": The camera image shows up immediately and stays up as long as I want.
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See my journal for how to record the video from the rear camera.
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See this post on disabling the "Backup warning" text:
http://www.subaruforester.org/vbulletin/6745121-post38.html
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(BTW, the Model X I get to ride in occasionally is very fast, very futuristic, and very out of my price range)