Although
this Tech Tip is entitled a "Buyers Guide," it may help you with determining some of the things on your 60-66 truck since Woogeroo broke it down by GMC and Chevy.
You'll probably find like most of us, the more you learn about anything about your truck, the better off you will be.
Welcome to the site. Ask and ask and ask. We are all here to help.
Peggy M