tl;dr
I believe that conspiracy theorists are a "type" just like say, schizotypy in fantasy prone individuals. It isn't simply that they are defectively processing information that others process successfully, they are processing information in different ways. Some of those peculiarities from my brief notes, i) anomolous data is evidence, ii) other conspiracies are evidence for this conspiracy, iii) certain truths are stigmatized and being covered up, iv) that it’s stigmatized and condemned by the mainstream is evidence of its truth, v) lack of proof is proof of the conspiracy, vi) disconfirming evidence must have been planted, vii) beliefs come before the search for evidence, viii) a common approach to all questions and conspiracies.
I do see a kissing point with fundamentalist religion, but one that is merely incidental. Different ideological communities coalesce around different principles for acquiring, evaluating, and sharing knowledge or belief. A scientifically oriented community is less likely to put stock in what an authority states if that authrotiy is in conflict with previous belief, however, a faith community, or a politically conservative community may be more willing to acquire the new knowledge provisionally despite the conflict. So yes, I believe CT theorists resemble fundamentalist religion in that they have a different set of epistemological standards. However I don’t believe they share much beyond that, except insofar as some of the epistemics of the two overlap.