That's a fabulous way to add some interest to a pelmet. Was this part of a whole room styling or just to add a bit of pizazz? Do you think a similar technique could be used on the wall unit of a split system air conditioner? The plastic often turns yellow over time, and this would a great way to cover that up. Obviously, you'd need to avoid covering any sensors, vents and buttons, but apart from that, I can't see why not.