Should curtain/valance rods be hung above the molding or underneath the molding right above the cup? There is a 6"-8" molding above the window and I don't...

There is a 6"-8" molding above the window and I don't know weither to dangle the valance at the top or under the molding only just above the glass. The home be built in the Late 1920's if that help.
Answers:    Since the home is from the 20's you may want the moldings to show if they are ornate and accentuate the room. If not put them superior ,even to the ceiling , that would make the window look larger.Try both ways and see how you like it. You hold to live there.
I suspend it above because you can always achieve longer top curtains. If you hang it below you can see the molding and it won,t look professional.