That is sweet! While your there with the materials you may want to make a smokenator type deflector. Flat Round bottom to match the curve of the kettle with one side folded up to bank your charcoal behind.
What the world really needs some to design, make, and sell is a SS bracket that would prop the WSM door open in the upside position. It would need to be a simple on peice design and be universal to 14, 18, & 22 wsm's as well as work with stock and aftermarket SS (Cajun bandit) doors. This would slide on the bottom of the door opening and allow for easy rigging free modification free High Heat cooking.
Think about it. I'll take 3!