Interaction designer, web standards advocate, Drupal themer, father of 2 boys, etc.
When the instructions say "Rotate the display assembly up until it is at an angle of approximately 45 degrees." they really mean "TILT THE HOME BUTTON END OF display assembly up until it is at an angle of approximately 45 degrees. Looking at the picture makes this step brain dead simple, but if you were using another iPhone to read the directions it would be easy to miss.
I successfully completed these steps to dry out a wet phone. While everything inside was dry as a bone, I never did remove the battery since the adhesive was so strong.
I found the spudger far too weak to even attempt the removal of the battery. Instead, I used a folding bone (something I've had for years that's used for making perfect folds in heavy printmaking paper) however, I was still bending the battery far more than I was comfortable with. Since my mission was not to mess with or replace the battery anyways I just left it alone.