I decided to make a male plug of the actual shape of the tunnel I wanted by making cardboard cut-outs spaced every 2". I used 2" because that was the thickness of the foam I had on hand to fill in the spaces.
Once I got the shape of the tunnel roughed out, with about 3/4" clearance around the bell housing and transmission, I transferred the shape over to 1/8" plywood ribs.
The stock trans tunnel/floorboard/toe board that Outlaw provides with the Willys body is more or less a universal style, with a very big hump for an auto transmission, which most everyone uses. Since I have a Tremec 5-speed manual trans, I don't need that big of a hump.
So, I decided to cut out the existing hump and fabricate a new fiberglass hump that closely fit the transmission I was using.
The first pic shows the stock tunnel. The second pic shows how much of the tunnel I cut out, and the third shows how much space I could save by making a smaller tunnel.
Here's the finished tail light installation, and a coat of primer applied. I plan on painting the Willys a very dark burgundy color, so these lights will almost disappear into the bodywork, blending in and not seen until the lights are turned on.
Also seen in the third picture is an LED third brake light I had installed directly under the rear windows.
These three pictures are construction photos by Posies. The body is cut out in the shape of the lens based upon a template supplied by Lambert. The lens is glued to the body from the inside, along with the prism material. Body filler is added as needed to the outside, and the entire lens is sanded down to match the body. Later on, the lens will be masked off and the body painted. The "lip" between the paint and the lens will be leveled out by successive coats of clear and sanded out for a seamless, flat appearance.