I built mine with wood and covered it with vinyl, easy job. Screwed it to the metal center floor with four short metal screws. I also added a short curved rod at the front of it to act as a cup holder. I did have to add a short seat belt extension from the floor so the seat could still be moved back and forth.
I love the raised armrest when I'm driving. I recovered the top lid with black diamond cloth as it is cooler than vinyl in the sun while driving. Car is temporarily in shop so I cannot show you pic of that.
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