Yea that Furrion kit is junk.
I have been using this setup for years and moved it to several different campers. You can also get a 7" Monitor on amazon for like $25. You can flip the image how you want.
I used the hole where the furrion camera would go on this latest camper we bought.
Here is the Monitor I use...
I don't leave the Monitor hooked up in the truck all the time. I just set it up in a pocket on the dash of the F150 and I use a Dive Weight to hold it in place. I use Velcro to mount the RX of the Camera to my back window and run power and coax under the seat up to the monitor. I leave the RX and cables in the truck. The Monitor has a quick DIN plug to add it quickly.
I also rewired the power from the camper to the camera in the back. The furrion setup uses your lights circuit to power the camera. That's just stupid. I have a switch in the camper and can turn power on to the camera when ever I want.
If you need more pics let me know. I will put in my truck and take some for you.
You can kinda see the camera on the back here.
I just went out and took this pic.