In other words, it should be the same, just that now the master files (nearly all jpegs) are just situated within the Aperture Library instead of the i Photo one. that is, deleting the i Photo Library before relinking? (I thought if two i Photo Libraries existed, it may not allow me to relink to the external correctly). Aperture 3.3 (or later) and i Photo 9.3 (or later) use a new library format that lets you open both i Photo and Aperture libraries using either application.
I began the process of moving my nicely organized master files for my Aperture 3 library to a fresh drive.You can do this for individual photos, entire moments, or custom selections as you browse through your photos.Note that copying in this manner may cause Photos to briefly hang and show your cursor as a spinning beachball, but do not interrupt the process.At the time, I was an extensive user of i Photo (people really underestimate how good that software is!), and was scared to mess with the library, so I imported it as a referenced library into Aperture.Do this for a different library, and you will now have two Photos windows on your screen with different libraries open.