Mod updated for 1.6 game version.

Harvester now have beacon lights (thanks to Todor Alin)
Tractors now work from 5:00 till 22:00 (thanks to Drive Safely for Guide )
Tractors not spawned in cities (added traffic_rule.sii file)
But they can spawn on divided road.
Default harvester have own sound.

PS. Mod is not compatible with ETS2 version.

Credits:
Piva, Todor Alin, AlexeyP, SCS