That's the way I did it too. I put a piece of packing tape from the screen, over the top of the phone, and onto the back. That kept me from putting any pressure on the ribbon cable should the phone slip and the whole screen try to lift away from the backing.
It should go without saying, but anytime you are handling the LCD, try to only touch the edges. Otherwise you'll be scrubbing fingerprints for 15 minutes. Not that I'm speaking from personal experience or anything.
Do not be surprised if your logic board doesn't lift up as much as shown here. The three antennas limit its motion. I worked in a pretty tight space in the next step.