Two shots of my brother, approximately 30 years apart. Had much trouble trying to get the faces to be the same size, no matter what I tried. Any hints? Can you resize layers once they are pasted into the background?
At this point, the only thing I could think to try is the 'Magic Wand' tool to grab the red, then invert your selection, copy and paste as a new layer, then lasso around each face and create a "copy-paste" new layer from that... Now you have layers again (sort of) and can "Transform - Scale" from there. I am not sure how well this will work though... But I guess its worth a shot. :-)