Problem with lights at rear of truck

Installing new light assembly for Volvo 780. I purchased it at a chrome shop. Cut and grinded it last night to fit my Volvo. The assembly has 4 lights and 2 flood lights that I intend on using for reverse lights. The assembly worked properly until I was driving my truck from the garage. The 4 ways work and brake lights, however, the parking lights on it stopped working all of a sudden. Like when Im driving with head laps on, the assembly has stopped illuminating leaving the truck without lights in the rear. The 4 ways and brake lights only work. What is the problem? Any help will be good. Is there another fuse panel I should be looking at besides the dash fuze panel? I really need to get this fixed today.

 

I sent you a thanks and also a thanks to Pablo from reading one of his earlier posts. The positive battery connection had a little corrosion on it... I cleaned then reconnected and when to back of truck and lights were working. Ill now start working on the reverse light issue on another post.