My assessment was based mostly on hostility expressed by my Dad and many freepers & other conservatives I've known through the years towards the journalists on the show.
The General Westmoreland defamation has been extensively covered here at FR, but there were other famous controversies about the integrity of their reporting as well,(See here at WIKI, scroll down to controversies.)
Even if this is a hatred for the 60 Minutes/CBS news that predates my birth - I still think knowing why Conservatives hated these shows will help me understand the times they lived through, nonetheless.
The Vietnam war one may be the sore point in that many identify being pro war as right wing and anti-war as left wing even though Republicans ended the war and Democrats were the ones who started and escalated the war (though the Republicans wanted to end the war with honor which is probably a major distinction?).