I don't have any personal experience/knowledge in this regard. However, I highly doubt that Canada would be able to know that you overstayed in the US. Even if there is some kind of an information sharing system going on due to terrorists and stuff, why would they even try to check your info? As far as Canada is concerned you would be a Nepalese citizen applying from Nepal (who just happened to have visited the US for 1 month 2 years ago). It just doesn't sound reasonable or probable that Canada would try to check the immigration status of anyone who has ever visited the US unless there's a red flag. Again, I don't have any personal experience but it just doesn't sound reasonable. Moreover, in the worst case scenario let's say they somehow find that out, what's the worst that can happen? They won't give you a visa, that's it.

Do what you've got to do, bro. Good Luck!!