I think you need to assume that there is glue present and apply heat anyway. In my case the cable was not glued to the board but the connector was. So when I tried to gently lever the connector up, the cable ripped off the connector.

If you look at the picture shown in step 21, you can actually see the glue on the connector.

"The battery isolation pick or battery blocker is an outdated way of isolating the battery, as you risk damaging the battery pins underneath the logic board."

As the previous comment says, if this is an "outdated way" then what is the up to date way?

If you just want to replace the screen then skip this step and all the following steps up to Step 13.

I’ve followed this procedure several times trying to fix a dodgy screen on the same laptop. After the 4th time I realised that you do not need to disassemble the base part of the laptop at all. Just skip to Step 13, remove the 2 hinge screws and pull off the black screen surround. It needs a bit of jiggling but its much, much easier than trying to fight with the 3 ribbon cable connectors for the keyboard.

If you do actually need to replace the screen cable, then you have to follow the complete process.

Double sided tape might work but does not provide the same level of sealing round the edge of the screen. Any wetness round the screen will wick under and get into the electronics. You should use a new properly shaped glue strip.

This photo does not show the original glue strip round the edge of the bezel. When you try to lift the screen the glue strip will be stuck to the glass is some areas and the the bezel in others. The 3 strips shown are not orriginal!

Very small flat blade screwdriver under the edge of the connector with wires worked for me. Just needed a very gentle twist or wiggle. Suggest removing 3 before 2

And when re-assembling use the slot to push the connector back in.

The step misses out the cable going from the top of the screen to the camera circuit board. The connector on the camera board has a little slot. Use a flat bladed screwdriver to push the connector apart.

I found 2 black plastic blanking discs fitted over the screws. Just prise them out with something pointed. Looks like they are glued in so may need a dab of something to re-attach them.

The sides and front edge of the top panel have a lot of moulded in clips holding the top onto the bottom. I needed a spludger to lever the sides of the bottom case out to release the clips from the top