Paint Runs!!!!!!!!

Sorry I didnt read all the posts but it might have been said.That being enamel:
1.you can"t just tape it off and repaint that area especially metallic
2.even if you sand it down you will get the wave effect
3.if you try to just spay over that area alone the metallic will not flow with the rest of the car.
Its a shame to cause the rest looks pretty good.
My advice would be to use base coat and clear to reshoot it.the base is a little more forgiving if you have to wet sand a run.
A cheap route would be to wet sand that spot and reshoot it lightly to hide the wave but not biuld up the metallics and cause a dark spot.You could also tape off around it sand and paint then sand the paint edge from the tape then clear coat the whole car for a smooth shine.