Getting a HN clone up and running isn't too bad, and the version of news.arc available is very stable as is. Also, the folk in this forum are very friendly and willing to answer questions. I don't think that getting your HN clone up and running would be much more difficult than any other forum.
Tip: if you are looking to customize news.arc, I would start by working it out of the table formatting and into CSS. If not, it's a pretty rigid beast. It's worth the effort, and would also be a good way to get familiar with the code.