...These are the correct HELLA lamps used by Porsche on the 914-6 GT https://pbase.com/9146gt/image/22265154/original to illuminate the car numbers https://pbase.com/9146gt/image/22237412/original. Essentially, the same light used by the early BMW 2002 series for the license plates.

Switch installation idea https://pbase.com/9146gt/image/128387752 I could mount the switches recessing them towards the inside of the ash-tray cavity, maybe forming a small 'half-moon' aluminium cover to follow the same countour of that section of the upper dash. Mmm....