Thanks Longbox, that is so simple that I feel stupid for not thinking of it. I added the measurements up, there is only 1" difference. The 1966 assembly is 1" longer. I don't see why that couldn't be accounted for by turning the tie rods in a little more into the adjusting sleeves.
Just to be absolutely sure, I asked my friend to get me a stud to stud measurement of one of his tie rod assemblies on his 1963 C-10. I still have the original tie rod assemblies from my 1966 C-10 assembled. I will compare lengths.
Seth K. Pyle