On my 41 P/U on the left one, I have an "L" shaped piece of stamped steel that is attached permanently to the bottom stud (either with a large rivet or maybe it is a stove bolt that has the nut on the other side of the cowel) The other hole goes to the top stud and is secured with a nut.
The purpose of this steel shaped piece is to secure the battery.
The one on the right side holds the wireing harness.
Al