Suggestion: When your Post/Question is not exactly concerning the 'thread' you're in, please post it as a separate question. Otherwise, it's easy for us Follow-uppers to overlook your question. Usually, we're not looking for unrelated questions in a 'common thread'. (You just got lucky w/me.)
Now, on to your question. Go to Is This Job For Me?. On the right side is an installation guide, one of whose items is Soffits. If it's not easily understood by you, then a pro may be in order.