Restoration purists look away now.
I have never been keen on pop rivets, because they are devils to remove and because they are not exactly cosmetic.
On the other hand I do not like filler either, and in the case of my landie, it had been much used on top of varios bits of plating tacked on with the ubiquitos pop rivets.
I am contemplating using very thin aluminium (cut from food tins) and simply gluing this over some of the holes just to keep the weather out.
I reckon that this could easily be removed if I decide to go for something more substantial.
As for the load area, It's far too much trouble to replace the lot, let alone the hassle of sorting all those terminally seized bolts. Chequer plate is uneccesarily expensive, and varnished plywood will do just as well, and is not going to react with anything either.
Ahh but that is a fire hazard I here you saying, well so are the seats and wiring.
Now for a few oak beams for the chassis :) (not)