When I purchased my 84 C22 all the interior trim boards had been removed for refinishing. I want to finish the job and put them back up. Here is my question. The trim boards for the cabin trunk/shelf areas are not identical. One has about a 4" notch with two more 1/2" notches on either side of the large one. These are located about half way down the board. Which side does this board go back on and what in the world are those notches for?