4: The screws that retain the headliner at the front are a machine thread and a specific length. Installing the front-bow material retainer screws during assembly can ruin your day. The screws can go through the top material if the top fits tightly. We run our fingers across the outside of the top in this area before we remove any screws to make sure the correct length screws were in place. In many cases, the screws are incorrect if the top has been previously replaced.