I don’t have an open Mark II for a photo but IIRC I only put washers on the bottom. The side mounting points/screws should be enough. The washers just help extend the head of the screw to hold onto the plate more firmly. Hope someone can come in with visuals if you need that but I only recall needing two washers somewhere near the bottom.
see how he uses washers on the screws toward the bottom of case. not really needed on the sides.