If we didn't have every frame of these movies memorized and we were seeing them for the first time I doubt you could show any of us a photo of the 1941 Wolf Man and pick Jr. out of a lineup as the actor beneath the makeup.
I agree. I've spent time staring at photos of the Wolf Man, trying my best to see Chaney's face behind it, but I just can't do it. I think it's the changes to the nose and mouth--particularly the mouth--that make it hard (for me, anyway) to recognize the Wolf Man as Lon Jr. I can see elements of Del Toro in the makeup above, but that is because I know it IS Del Toro.