Adding that rubberized square patch that sits on the inner fender apron to insulate the metal from the positive battery cable.
Just for others viewing San Jose used the black plastic "plugs" or staples to retain these shields. When the car was built determines which hardward was used. Often these inner fender panels were replaced due to damage by things like battery related rust so you can't always use the panel as a guide to which hardware was original
FWIW, when I was restoring 6S1487, just the staples were there. I found that the staples seemed identical to those used on the splash shields. They probably used the same industrial staple gun to apply them. You can install them manually and fold over from the backside.
My inner fender just had four small holes so they must've used plastic grommets. That must've taken one hell of a staple gun to get through that metal.