Backup cameras are simple. Mount high over the rear door, as centered as possible width-wise. One wire, usually black, will be a ground, can be connected to any part of the steel body (I would recommend taking off some paint where this ground is mounted), or spliced into an existing ground wire.
There should be another wire, likely red, that ties into the 12V to the reverse lights (will need a test light to determine which of the two is 12V).
Then there should be a video output cable or wire, this will usually be an RCA-type output, which plugs into your dashboard-mounted monitor and will likely require a cable extender to run the length of the bus to your dashboard-mounted monitor.
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