Clean the hole thoroughly to remove any debris, dust, or rust that could affect the fit. Use a wire brush or compressed air to ensure the hole is free of contaminants. Check the hole diameter and depth to match the specifications of the protective plug. A hole that is too large or too small can compromise the stability.

For metal plugs, thread-locking compounds like Loctite can prevent loosening due to vibration. For plastic plugs, a compatible adhesive can enhance the bond. Apply the adhesive evenly along the threads of the plug or inside the hole.

Check for any signs of misalignment or unevenness. Ensure the plug is flush with the surface and does not protrude (safety hazard). If necessary, apply additional sealant around the edges to enhance protection against moisture and contaminants.