CARL has made available a declassified (previously Secret) study, dated 29 Dec 66:

A Typical Hostile Guerrilla Force, 1970-75
This handbook is designed to provide basic guidance for agencies conducting combat development studies, war games, and field experiments involving a hostile guerrilla force in the Southeast Asia area in the time period 1970-1975. It is based on information derived from current area studies, afteraction reports, captured guerrilla force documents, and current intelligence studies. It reflects projected tactical doctrine and estimated weapons and equipment which will be available to a typical guerrilla force in the area and time period described.
Complete 80 page document at the link.