This is probably a basic question but our club just got a PA28-180 added. The manual calls for the start to be on the left magento very specifically. The other planes I have flown have both been 172s (a 1964 172D and a 1976 172M); this Cherokee is 1963 but in my limited experience I have not encountered the start on a specific magneto and wondering if someone could explain why. I have no issue with the procedure just curious and trying to understand the reasoning. Thanks in advance.