I don't think Scrooge is either one (conservative or liberal). I think he's just selfish, mean-spirited, and greedy to a degree that makes it easy for us to see. That isn't a trait that is intrinsic to either conservatives or liberals, though I suppose in more recent years these have been touted occasionally as virtues by people who call themselves "fiscal conservatives".
But even these "fiscal conservatives" are probably being somewhat mislabeled. Just because someone is wealthy, and wants to stay that way, and therefor tends to strongly support the status quo (the real definition of a conservative) that doesn't mean that being wealthy, greedy, mean-spirited, and supporting the status quo is the full and only definition of conservatism.
And in the story, Scrooge is wealthy, greedy and mean-spirited, but he is not depicted as being particularly supportive of the status quo, which is to my mind the defining factor of "conservatism". So I don't see Scrooge as being particularly conservative.
As to Scrooge being a libertarian, I don't know what to say. Libertarians are mostly just idiots, and I don't see Scrooge as being an idiot.