This is a mount for my 2010 F-150 without the navigation screen. It fits in the slot where the radio screen is without any extra attaching method needed. I am printing on an ender 3 so I split it into two parts but I also have the single piece attached if you have a bigger printer.

Just Updated the design a little bit to add more strength.

With my first PLA model, I melted the two pieces together and they hold well but it is a little warped. The tablet fits great and there is actually no need for anything else to hold it in place. I just tested driving up very steep roads and hard accelerations. The tablet mount did not move at all because of the lip that it wedges into and I am happy with just letting it sit in place. This meant for road and light offroad use. If you jump your truck and it falls out, use adhesive or magnets like I originally planned. I would call this a success but I will continue to test it. The PLA will probably deform more in the sun so when that happens, I will print it in PETG or ABS.

I made this video before I had the printer about how to use the tablet as navigation because it doesn't have a built in GPS. Here is the link if anyone is interested in that.
https://youtu.be/LthST2vRY_w