I know it's a little late, but if you haven't already decided what to do about the skulls, I would say drop them completely. You might be tempted to just drop the load you are using and up the reps, but I think you need to give your elbows a rest. This is one reason that I try to avoid doing lower reps (and never negatives) on lifts that involve the elbow joint. Too easy to screw up your elbows.