Rearview mirror camera
We have a 2016 Cambria on a Ford E-450 chasis. It had a regular rearview mirror in the middle of the windshield, but there is no rear windows. Regardless, out of habit I found myself glancing at this mirror every so often after 55 years of driving. It was very frustrating. There was a decent rear camera view in the radio, but it was not my usual eye scan and had to be reset if I hit the turn signal. I found what I needed on Amazon, it was the Wolfbox G850. The monitor screen fits over the rearview mirror with straps. It has a forward camera on the back of the screen and I ran a cable back to the rear and mounted it's camera. It is powered via a USB-C connection and has a GPS antenna as well. Add a micro SD card and it records video of front and rear with time stamp and location coordinates. All in color and satisfies my compulsion to regularly check the rearview mirror. This has multiple options, display is touchscreen and I can see front, rear, or split. Cost was about $200 and it took some effort to run and hide cables, but really worth it.