BP_Sky Opacity for space background?

I’m new to UE4 and still struggling to learn some basics;
What I’m trying to achieve is an sky with a bit of galaxy/stars in the background, so I bought SpaceBox Dim in Blueprints - UE Marketplace
I have :


And what I’m trying to achieve :
(Photoshoped by placing them on each other)
Basically I just need the sky to be a lil bit more transparent to show the huge space box in the background while maintaining the suns and cloud effect
what should I do to achieve such effect?
thank you very much in advance.