Welcome! Here is a great link on year correct hubcaps:
http://6066gmcguy.com/wheelcover.html
If you are looking for some nice 62-63 clip type caps, Rustbucket had these for sale:
http://6066gmcclub.com/showthread.ph...light=hub+caps
I kind of like the 62-63 caps more than the 64-66, but that is just my opinion. I looked long and hard for the 64-66 nub type caps for my 65, but no luck. I bought a set of the 67 caps and 69-72 caps as plan B in case I can't find any. Good luck!