I have a low voltage spot light on mine, similar to the ong landing light.
The bigger problem than the light itself is how to maximize the amount of
span you can see.  It is hard to get a light into the root so that you can
align it to the dihedral.   You are probably better off with a flood and
then you will still have to pay attention how you aim it.  Also consider
that the light itself may have some ice on it.