Does anyone know for sure whether or not all the plastic(front and rear fenders,tank cover and the hood) for a 2000 Warrior will fit a 1990 Warrior?

It should!

I think the fenders will fit, but the headlight on the 2000 Warrior is in a different place than on the 1990 Warrior, so the piece of place on the front probably won't fit without some modifications.

I think the headlights on the '90 Warrior are in the same spot as the '00 Warrior. I thought they changed that in maybe '89, but I could be wrong.

what year did they change the plastic