Gradient transparency of normal map? Is it possible to make the normal map gradiently transparent? I need to do this Making Vertical Gradient, then make top half transparent , but not for the object, only its normal and specular map. 

Why? Because I have one object with 2 different maps. I have got rid of the seams with texture paint, BUT the strength of the normal map differs, so seams are created. So I need to make them transparent where they meet, in order to get rid of them.
Channel the gradient into a MixRGB node where you mix the normal map color with a neutral blue color (and by neutral, i mean R=0.5, G=0.5, B=1.0, like the default input of a Normal Map node). You can of course use this to blend between the two normal maps too. To blend between normal maps correctly though, you should use Split XYZ nodes, add R/G values and multiply B values between the maps, and then do Combine XYZ again.