What is the light (not illuminated in your photo) directly below the headlight indicator?Here are the photos I mentioned.
If you look closely at the back of the panel, you can see that this panel is
used for the M27 and M26 series tractors. The M27 is the CK25/30/35 in the
U.S. I do not know what other models are in included in the M27 series. I
suspect the M26 is the CK20. The DK tractors use a different panel, from
what I remember.
In the other photo, 2 of the "extra" mystery lights are lit up green.