Here's what I did to cure poor lighting.
The light units are available from NAPA.
The combined current draw is 7 amps.
I put a broad beam fog bulb in one side and a utility bulb in the other. This spreads the light pattern from directly in front of the tractor out to about 200 feet.
With this type of bracket, it allows the light to be bent back if you run into a branch etc. and not be broken off.