I count 159 total games. No interleague. Odd number of games works, it is just that teams play different numbers of home & away games. So 159 may split 81/78, 80/79, 79/80, or 78/81 (ideally the middle two).
A more conventional option would be 162 games like you describe except with 1 more game against three division opponents. The 159 is fine if you do want that, but I just throw out this other option for your consideration since it will probably be a couple days before I can finish this.
I have trouble remembering, but I think schedules need to be imported during the preseason.
This post covers some details on importing schedule files.