I installed a Viofo A129 Duo. It's 2 separate cameras, main one in front and a little one goes in the rear. They also have a A129 Duo IR model that has IR functionality on the little rear camera. It can be used looking out the back window or rotated inward to record the interior. It also comes with a smaller rear camera cord so you can mount the rear camera on the front windshield separate from the main camera and use it for an interior camera.
They just released the A129 Pro version, which is a 4k model.
I mounted the rear camera to the plastic trim around the rear window. It comes with a 6 meter cord which would probably work if you run it through the headliner, but I didn't. They sell an 8 meter rear cord that I used. Mounted the front main camera just to the passenger side rear view mirror mount so it is hidden by the DOT MATRIX pattern on the windshield with only the camera lens hanging down below them. It is also not visible while driving, the mirror blocks it. The rear camera cord is ran tucked into the headliner across the front to the passenger side, down the A pillar to the floor, then ran under the plastic trim door sill covers to the back. Once at the back ran it up to the top of the trim at the center of the liftgate opening and ran it through the rubber boot to the liftgate. I made a notch cutout on the edge of the trim piece at the top of the rear window glass for the cord to come through and mounted the camera there on the trim.
Its at the top center of the window and still faces back/downward when the glass is opened, but will point upward when the liftgate is opened. It could be mounted to the trim that goes across the back headliner, which wouldn't require fishing it through the rubber boot and removing the lifgate trim, but it would need a spacer to hang it down low enough to have a clear view out the glass. It could also be mounted to the rear glass, but you would need to leave a loop of cable slack for when the liftgate or window was opened. I wanted a cleaner install and not any cable loops hanging down.
I'll get pics later today