Question about OnMouseOver and prefabs that are close together (overlapping)

Ok, let's say I have a simple prefab that is just a cylinder. I add three instances of this prefab to the scene, such that each cylinder has a slightly larger radius and they overlap (if you look at the scene from overhead, it simply looks like a target with a bullseye).

Now, let's say I want to be able to select a cylinder with the mouse. So, I add a script and use the OnMouseOver function. Problem is, no matter where I click (within the area covered by the three cylinders), the largest one is always the one that gets selected. So, if I click the smallest cylinder (the one that looks like the bullseye in the target), the largest cylinder still gets highlighted.

Any thoughts as to how I can fix this?

I figured it out... duh. I had to change the Capsule Collider to a Mesh Collider. All good now. Sorry for the trouble.