Like GFraser1965 already wrote, there are different "driver" entries possible.
In rF1, where the "driver", if present, isn't automatically shown in cockpit-view, you normally have the instance=body to implement a driver for the outside-view of the car and the instance=helmet for the helmet.
To e.g. have a complete driver, or just hands on the steering wheel or feets, visible in cockpit-view, you can use the steeringwheel instance for e.g. hands that turn with the steeringwheel.
Or you add lines into the cockpit instance for the parts that you want to have visible in cockpit-view.
So that question can't be answered in general, it always depends on the mods structure.
Just find out which gmt are visible in which view, to be able to change them and/or find the entries in the gen file, to delete them.
And in some cases, like the turning driver hands, you will have to edit the gmt file, to remove the hands.