This mod allows a full control over the head and dash cameras.
Set the FOV using the preferences in-game menu and move the unlocked seat positioning with the numpad.
Note: unlocked means you can also go outside the cockpit 3d model. Which ofcourse would destroy the game immersion. Use with brain
This mod adds a wider range for FOV, so if you play with fov 1.0, probably you will have to decrease it in your in-game preferences menu. I suggest 0.7.
The near-plane clipping is corrected so you can go closer to the windshield, without cutting the glass polygons.
Tested with DiRT Rally v1.23
Looks like it is not possible to do the same with the two chase external cameras, because the actions bound to the numpad keys are hardcoded in the exe and they only affects cameras with "type=head" tag.
I could make the FOV slider work with chase cameras, but i don't think it would be useful. No point to increase FOV if then you can't move the view forward: the car would look too distant, and unplayable.