I made a narrow one for a carb setup as it would have stuck out th eside of the hood. Buy a filter. I used an Edelbrock and squeezed it together. Trace it on MDF. It makes a cleaner edge than pine. Then cut a piece of aluminum, .060" or less a 1/2" larger all around than the wood. Clamp it in several places and start pounding the edge down. When you get done, you can trim excess. I flipped it and milled it. Nice to have tools. For the bottom I used the same wood and added a hole the size of the carb inlet and cut a smaller hole in the plate and hammered a throat just to dress it up. Or you could just run flat plate.
