Cast to multiple objects

Hey, I’m trying to set an event (currently a key press for testing) to change a material of a mesh in a blueprint which I have managed to do.
But I have multiple copies of the same blueprint around the level all of which I want the material to change.

So I have my level blueprint:

And my light blueprint:

What I need to do is have all of my Light1_blueprint nodes link to the object slot on the cast to node but I can only link 1 Light1_Blueprint node to the object slot.
Is there any way I link them all to the object slot?

I realise I could do something like this but It takes up a lot of space and time. I also realise I could organise them in a macro but it would still take up a lot of time.


Thanks to Fen I managed to get it sorted.