Placement of humid hides

[Homebody]

...But I have found my humidity is lacking and I've decided to create humid hides.
My question is, do I replace one of their hides?
Should I put it under the basking spot?

Don't replace either of their hides. The humid hide should be in addition to its cool and warm side hides. Don't place the humid hide under the basking spot. It'll dry out too quickly. Place it on the cool side.