I didn't make my first solo record until 1981 so I don't have any 60's or 70's recordings but I am working on a large boxed set called DUST to be released next year the 20th anniversary of my first solo record.
Color is a plastic means of creating intervals... color harmonics produced by special relationships or tensions. We differentiate now between formal tensions and color tensions just as we differentiate in music between counterpoint and harmony.