Maybe I can add something. I have what I blieve are 60's vintage Koni shocks on my '66 Mustang GT. I also have the original paperwork from Koni which includes the adjustment procedure. I will post it below.
This is for what Koni calls 'Special "D"' Shock Absorbers. I believe my shocks are what were originally used on the early Shelbys and were probably put on in the 60's by a previous owner (although I could be wrong as I haven't really researched it). I know they were not standard even for K-codes. I had the front two rebuilt by Koni North America recently as one was completely frozen. Hope this helps.
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