Yes the Mk1 had a valance at the bottom rear.
It also had a stand that extended from the lower forks and clipped on at the rear of the guard.
The top curved around steeper towards the top of the tyre than later models and looked like a "parrots beak".
There is a difference in the valance between Mk1, III and 1V also the depth and profile of the sides.
If I get time, I will mail you some pictures of each.
Tom