Yes, the ones I have are from the 80's.
I'm not as familiar with the older 1 ton dual wheel trucks as I am the older 1.5 and 2 ton trucks.
But My thinking was that if the 1.5 and 2 ton trucks used them back then and still did until the 90's when they dropped that bolt pattern. And if the somewhat later model 8 lugs used them then the older ones probably did too, although sounds like not always....
Using the later model clamp plates seems like a good idea to me. Or using original parts is a good idea. But guessing what might be different or better is not a good idea if you don't first understand what the original solution was. Also knowing later model factory solutions to the same problem also helps make the best decision on what to do.
Sounds like you had a problem of some sort in this area recently, figure out what the right thing to do is first before moving on.
Grigg
