Everything worked out as advertised. On the issue of whether to buy a heat gun or not, along with the predicted one hour plus if using a hair dryer, I watched a Utube video where one guy measured the temperature needed to loosen the adhesive and it's around 160-175 degrees F. Using a candy thermometer, I measured the temperature of my wife's Revlon hair dryer. At the hot/high setting, it reached 150. On the hot/low setting, the magical number, 165! The low or high setting is just airflow and with the lower airflow on low, you get a higher temp at the nozzle.
The instructions warn against exceeding 300F so that's telling me the hair dryer cannot hurt the phone. I applied the heat from the hair dryer, hot/low, 1/4" from the edge of the screen for a bout 30 seconds. I had the broken glass off in about 15 minutes from when I started the project.