How do I connect all these in material?

I downloaded a free texture from TextureHaven containing AO, bump, diff, disp, nor, rough and spec, all willy nilly i connected them like this (RGB channel): diff - base color, spec - specular, rough - roughness, nor - normal, bump - world position offset, AO - ambient occlusion, disp - pixel depth offset.
I probably got some of them right but bump and disp are definately not right since there is quite a difference in result between the preview on TextureHaven and in UE4.
Is there a guide or something that goes over how to use all of these maps correctly?