You know how you have that linked model, and there’s that one pesky element that you don’t want to see. Ever? Just like you can hide individual elements in your model, you can do the same to elements in a linked model. Mostly.
The trick is getting it. This is where you good friend TAB comes in. Just TAB down to highlight the element, click to select it, then do the usual right-click to hide element in view.
What is that? The option is grayed out? Well, here comes the aforementioned “mostly”.
If you have done any overrides to the model’s appearance on the Revit Links tab of Visbility Graphics, you lose the ability to hide individual elements. It all has to be “By Host View” to allow that.