Having Issues with Camera Viewport Rect

I am currently working on a multiplayer game that requires splitscreen. I have looked up how to change the camera's viewport rect in order to acheive this, however, whenever I change the x or y values off of 0, it doesn't work. As expected, when I change the values to less than 0 or higher than 1, it stops working. That is not the problem.

I want one camera to take up the upper half of the screen and the other to take up the lower half. So I think it makes sense to set one camera's viewport's y value to 0.5 and leave the other at 0. I would leave the x and width values at 0 and 1 respectively and change the height value to 0.5. However, when I do this, all that happens is that both cameras take up the lower half of the screen. No matter what I set the y value to, it never moves the camera view's position in the screen unless I set it to a value that Unity doesn't like and it shrinks away my view or sets it to the scene view camera.
I can change the size of the screen that the camera takes up but not where on the screen that space is.
Any help is appreciated.