Thanks! Guide easy to follow. Change 2tb to a 4tb Seagate. Didn't want to mess with another brand because threads said that the rubber supports were a better fit for Seagate drives.
I just changed the 2tb to a 4tb Seagate. Awesome! Great pics and instructions. Now my A1470 has a working 4tb drive. Love it. 2tb - was running out of space.