Hi Chuck!
I purchased #4744 in 1976 with this lower areas paint scheme.
I don't know where that black curve at the front came from, but I have grown to really like the way it outlines/surrounds the turn signal pod and then flows into the center of the grill, and black has been added to the belt line of the fenders and doors.
I also like the way those rear "triangles" visually "kick up" the rear of the car, and overall I'm really happy with it's profile.