Mark Lane showed up in Jonestown a few days before the "drink the koolaid" mass suicide-CIA slaughter (take your pick, there are conspiracy theories there natch, I can forward the URL's for sites with volumnious documentation including the House committee hearings...).
He married the daughter of Willis Carto, the Liberty Lobby/Spotlight "populist". He's a lawyer for them. Represented them when they sued the WSJ for defamation. Cf. Larry Mintz, "The Liberty Lobby and the American Right, " Greenwood Press, published mid-70's.
Lastly a piece on Lane when he was early on in his notoriety was published in Partisan Review around 1965 or 1966. Has that sneering tone of the oh so sure Cold War Libs, but still take a look. (And on that tone cf. Diana Trilling, "The Other Night At Columbia, "her piece on ex-Lionel Trilling student, Allen Ginsberg. It's in her , "We Must March, My Darlings!" Also see her autobiography of her life with Lionel. What did Lionel say about the right in The Liberal Imagination. Hereb it is, "But the conservative impulse and the reactionary impulse do not, with some isolated and some ecclesiastical exceptions, express themselves in ideas but only in action but only in action or in irritable mental gestures which seem to resemble ideas." (Cf. The Conservative Intellectual Movement In America, Since 1945, George H. Nash, Basic Books, 1st ed. 2nd ed. Intercollegiate Studies Institute. Also Arthur McGovern book on neo-conservatism that Temple Univ. Press published. He is a DSA'er that has also published on Marxism and religion.