Most of out product pages for Mercury and Mercruiser part numbers have a "Where Used" tab. While this is handy to see what engine, drive or accessory a part is a component of it is not always 100% accurate. Many mercury parts have been superseded or upated to new part numbers over the years. And the "Where Used" tab only lists the engines or drive where that part currently appears. For example the 807151A14 is the latest version of the 807151A7 housing.
The problem is the "Where Used" for the A14 version does not show the earlier engines for the A7 version, even though the A14 is fully compatable. Depending on how long ago the original part was put in service it may have been superseded a dozen times. So the "Where Used" for the current number may not even exist.
Bottom line "Where Used" is usefull but not perfect. As always is best to confirm parts by using your serial number.