When I used to write regularly for anarchist periodicals, I would sometimes find a quote of Marx's useful. When someone can explain a concept better than you, heed way, and let them do it. Like Bakunin, I like Marx and have never felt especially compelled to be some sort of orthodox Marxist or Leninist based on reading his stuff. I just enjoy reading him, like I enjoy reading Foucault, etc. I admire the guy.
What I would notice early on is that when my pieces were published, references to Marx would be removed. I learned that sort of indirectly legitimating Marx was unacceptable by referencing him. This seems silly to me. I learned if I could find an anarchist who said essentially the same thing, and could quote the anarchist instead, the quote would pass and end up in print. As there is a lot in common between left-Marxism (by which I mean autonomous Marxism and more libertarian variants) and left-anarchism or class struggle anarchism, there are indeed many shared sentiments.
Foucault said he even "quoted Marx without quoting Marx" in one interview, if I recall. Just FYI, an ugly and unfortunate dogmatic sort of thing I experienced. I know for a fact it's the same way among Marxists for whom too much praise can never be heaped upon the Master (i.e. it would sacrosanct to quote Bakunin, even if he had some brilliant insights into society, which he does).
-B.