The hood is going to be 24 inches about the cook-top, so the bottom material needed to be non-combustible. I used air duct sheetmetal to cover the wood. I also made an inset box for the light to sit in. The seams in the box are sealed with gray high-temp silicone caulk. This was the first time I worked with metal like this, and it came out OK. It took the better part of three hours to just do what's shown here...
Here is the top side of the hood unit.
Once the fan unit was fully in, I put the the bottom trim and top mantle pieces on. The center part in the picture already had stain on it, so it's darker.
The final thing to do is stain and apply the carving to the front.