Check the following YouTube video:
View: https://www.youtube.com/watch?v=FjVgFTazOdw
Came up via a "tp-link archer c4000 router disassembly" google search.
And there are other similar videos as well.
Overall the same "open the case" concept(s) are likely to apply.
Watch out for hidden screws under labels etc. Commonly used to detect warranty violations by end users or voiding warranties if the label is torn or broken.
As always, power off and unplug before opening.