Capt. Wanabe":28xsyrmq said:
The correct order of install would be the flat washer, lock washer then the nut. Just like how you installed it on the right side. In that arrangement, there is ZERO current flowing through that washer, it is simply just part of the fastening system. The flat washer is provided because the lock washer will want to spin as you tighten it down, it can score and mar the surface of the ring terminal and/or get caught on the edge of the fuse, the flat washer just ensures that the lock washer can do its job and the nut can be properly torqued.
Looking at it again, I see its bare plastic on the stud, an additional flat washer before the fuse and ring terminal wouldn't hurt, no current flow there so it's totally safe to do so.