Hi, man. If you just stick a reflective shader between the image map and the object/surface, that should do it. To have more control to blend the reflectivity as well, make a reflective shader the child of a non-colour surface layer and put that between the image and object/surface.
Either of these ways should work fine, the second way is better because you can use the surface layer constraints and blending functions on the reflectivity, if you wanted to.
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