Hi Blue 50
This is a question I can answer because I am so old !
The rivets you are talking about with the hole in the middle are 'pop' rivets and they are installed with the tool that compresses them until the inside 'nail' like device breaks.
Is that right ?
The old style rivets were a bit like an ordinary nail.. a head that you put on an anvil or such and then flattened the other end with a hammer.
I find these rivets hard to find... and if anyone can give a source I would be really pleased. A chain store near me called 'Lowes' have a small assortment but not a lot or choice.
Good luck and nice looking truck you have !
Ter