Can you stick a small LED strip inside there and still have it out of the way of the ball and any switches instead? Maybe take the scoop out and then just feed the wire thru a seem or hole or make a small hole? Either stick the strip to the scoop somehow or maybe stick it to the underside of the play field inside the scoop area? If there's room...
Ehh, never mind that - the light probably wouldn't glow up and out, it's probably better to get it pointing up out of the hole somehow.