I'm looking for a plastic insert for shipping container corner castings. The insert should fit precisely into the corner casting and have a sturdy hole for a 2x4. Requirements: - Material: Plastic - I want a file to 3d print with PETG - Functionality: Fit into corner casting and provide a hole for a 2x4 - need the insert to fit in the top of the corner casting but have a opening in the top of the insert to snuggly fit a 2/4 - Design Specifications: Both precise fit and hole strength are critical Ideal Skills and Experience: - Experience with plastic design and fabrication - Knowledge of structural integrity and precise measurement - Ability to create durable, functional designs