I just went out in the gurage and looked at my 84 70. I went back and looked at my parts book. I think the schematics are screwed up. The page with the seat also has the part that goes under the fender, between the fender and the frame. The page with the fender has that plate. Without taking my fender and seat competly apart, I now think the plate goes on top of the fender, between the seat and the plastic, and the bigger part that goes between the fender and the frame goes on the bottom.
ATCnut
82 185s - sold
83 200x (hopped up)
84 200x (stock)
84 70 (lost this one to the DMV)
85 70 (soon to have lights, a foot brake, and CDI ignition)
84 200es (parts trike) - sold
85 350X (the best)
85 350X (siezed motor, dream of a poweroll kit someday)
85 250sx (frame was trash, got parted out)
86 250sx (the tractor)
86 250sx (a nicer tractor)
86 250sx (an even nicer tractor)
87 200x (parts trike, its really rough, a dog was chewing on it for a while)
87 250es Big Red (the tank!!)