Use this guide linked below understand where to place the iron under the screen. Step 4 doesn't seem to contain the proper images or details of this step here well enough.

https://www.youtube.com/watch?v=-OEXhxoT...

https://www.youtube.com/watch?v=-OEXhxoT... shows the repair and includes additional details about the area to place the iron.

The red circled screws have no part of this step.

You need to remove the rubber strip you see in the picture that's below and along the bottom of the screen.
Set iron to 450
Run iron along areas that coincide with the problem lines.
Replace rubber strip when done.

You should set it to 450, according to another repair demonstration.

There are two screws indicated but not mentioned and there is no ribbon cable in sight, unless it's behind that brown plastic cover looking thing. I have to assume I'm to remove the indicated screws and would see a ribbon cable behind it and under the screen? Otherwise, maybe you run the iron in between the two screws and the brown thing is somehow the cable? This is the most I've ever been puzzled by one of these guides. I'd just hope when I got to this part I'll be able to determine what's being said.