On my controllers, there was yellow tape over these? and in some other places as well? Why?

The middle bottom screw may have some form of warranty sticker on it if you have a Vive Pro wand (which is purple). Mine had this. Easy enough to remove and get on with it.

From what I can tell, there are two clicks on each side? one is quite easy, then the other one seems to require considerable force pushing down and on the side, I had to do it one side at a time and found two YouTube videos performing this step to use as reference. I have the vive pro wands and not the originals, so this may explain the difference. This felt very wrong to me.