Few options affecting driver model.

Shadowed driver

If you’re not using vertex ambient occlusion, another way to stop driver head from glowing (without occlusion it looks way too bright from exterior cameras) is to set a virtual occlusion sphere above driver head:

[SHADOWED_DRIVER]
OPACITY = 0.7       ; shadow opacity
OFFSET = 1          ; how high is the sphere above driver head
RADIUS_INNER = 1    ; inner fully shadowed radius 
RADIUS_OUTER = 1.6  ; outer not-at-all shadowed radius

Replace driver model

This particular tweak can be useful for a custom skin using a different driver model:

[DRIVER3D_MODEL]
NAME = driver_80  ; file name from content/drivers (without “.kn5” extension)

; Don’t forget to list to hide:
[DRIVER3D_HIDE_OBJECT_...]
NAME = DRIVER:HELMET_SUB0