How to open the display cover or remove water from display layers?

Ouch! Not good!

First the design of the display is quite hard to open as Apple designed it to be sealed. In addition I haven’t been able to replace the 2018 model displays with alternate displays. At best you’ll need a real Apple display assembly from another system as Apple doesn’t sell parts directly.

As far as the body being liquid proof not really! Your keyboard has just managed to capture a good portion of the spill now it’s still festering in the cavities within the keyboard and I’m sure some has sneaked deeper onto your logic board. Depending on what you spilled corrosive actions can slowly damage your system and mold and bacteria will grow in the spillage and over time will eat into your circuitry.

Now the tough part! You need to fully disassemble your system to at least clean up the spillage. The keyboard is not replaceable on its own. Just like the display Apple did a very good job making it extremely hard to remove it and so far there are no replacements.

The costs are adding up here … What to do??

First I would strongly recommend you make a full backup of your system using TimeMachine. As all you need now is your system dying to the point you can’t recover your Apps & Data. Next I would hunt down someone giving up their MacBook because of a logic board failure so you can transplant your logic board to their dead system. In the mean time you should avoid using your system as the more you use it the more you could damage could happen.

You might want to buy another system (low end version) to likewise swap out your logic board if you have one of the higher end models. Or, just get a new system clean yours and put it aside for parts.

I wish I had better news ;-{