OK, I took a look at the curved piece a little better and sure enough there is a hole just above, behind it. The hole could most diffently be for a drain hose for the vent.
So is the curved piece to cover the hose or to hold the hose? still a mystery to me.

I'm real sure the truck has kick panels because there is a small flange (about a 1/4" high) at the floorboard that looks like it is for retaining the kick panels.

Thanks for the input guys!

Regards, Kevin
1940 1/2-ton (Uncle Willie\'s truck)

Thanks for the help so far fellow Bolters!