Download the exploded view from
www.gasgasmotos.es and have a look.
There are 3 points that washers are required. 2 of which are on the L shaped rocker. The front pivot slides between 2 brackets. This is where the washers are required. The upper hole in the bracket is where the swingarm axle goes through. The lower hole mounts to the frame. The middle hole needs the washer on the inside edge.
Then the dogbone connects to the back pivot, and the shock mount to the top of the L rocker.
Make sense?