Casting between Blueprints Target?

So I want to make a connection between my FirstPersonCharacterBP and a Decal_1_BP. The goal is to make the decals visible or invisible with the press of a button(when the character has a special pair of glasses.

I can´t make it work.

I set it up so that the visibility of the decal-component is decided on a variable: HasGlassesOn. At EventBeginPlay the variable gets set to false in the DecalBP but can be changed by a custom event that I want to be able to trigger thru the FirstPersonCharacterBP.

I have looked at a multitude of tutorials on BP communication but I can´t get this to work. The cast or even node always complains about not having a actor or object connected, but I clearly says in the header of the node that “Target is Decal_1_BP”, so it knows where to cast but still it gives me error and I don´t know how to reference the target.

Sorry, I know there are probably loots of posts about this kind of topic but I can´t wrap my head around this.

Any suggestions on how I can solve this and what I am doing wrong?

Thanks for the suggestion, I will have to look up event dispatchers later on.

I finally solved it by hooking up a “Get all actors of class” setting it to the Decal_1_BP and then hooking that up to the custom event. Not sure if this was the best or most efficient way to go about this but it works for now.