I've just been through setting my triple screen FOV in AC after getting a new wheel. The results was huge with a big jump in realism.
I started with this article on driving position and set my seat, pedals and wheel at the recommended heights.http://www.ricmotech.com/v/vspfiles/downloadables/Driver_Position.pdf
I then did the following steps to setup the monitors and AC:
1. I positioned my centre screen as close to the back of my wheelbase as I could. This ended up being right at the end of the wheel base housing due to my monitor stand.
2. I then positioned the height the monitor so that height of my eyes were at the middle of the screen.
3. I measured the distance to my eyes. For me this was 700mm.
4. I then positioned each side monitor so that if I turned my head to look at the centre of each monitor then they were square on to my eyes.
5. The angle of my side monitors turned out to be about 42 degrees.
6. I then fed these numbers into the AC triple app. ie 700mm, 42degrees and the sizes of the monitors.
The result is that I get a perfect FOV for every car in AC without changing any of the driver view settings. I used to have to change the PITCH setting in every car. Now it is perfect using the default set by Aris. Also, I look through the steering wheel at the car's dash as you do in a real car. The sensation of car height is very real. You feel low in the KTM for example.