I have a 64" Kodiak from 1959 (which is very similar to the 1960) and I have it shooting pretty good at 8.25".
Many folks believe a brace from 7.5"-8.5" works pretty well, but some experimenting will tell you for sure what's best for your bow, arrows, and shooting style.
I love those 1960 Kodiaks, both in looks and performance.
Now, show us some pics of that bow, ok?