By necessity, we had to use an image of Bookhout from when he was a young man because that is all we have. We have no images of him from the time of the assassination or thereafter.
So, since we have to use an image of Young Bookhout for comparison, let's try it using an image of Young Ruby as well- for the sake of consistency.
What jumps out at me is that Ruby had much larger hunk of nasal tip cartilage than Bookhout- even as a young man. Bookhout had a VERY slender nose, and we see it on both sides of the lower set. So, the nose match goes to Young Bookhout, not Young Ruby who had more of a honker. Ruby had a longer forehead, even as a young man. The lips match goes to Young Bookhout because Ruby had a thin upper lip and a pouty lower lip, which we don't see on Bookhout. We can't see the older Bookhout's eyes, which were deliberately obscured, but notice that the depth of the eyes and the orbital ridges are an exact match between Young Bookhout and the older man. The head/neck relationship-the way the head is balanced on the neck- goes to Young Bookhout too. Ruby had more posterior cervical tension that caused him to raise his chin more. In other words, the pitch of the head is exactly the same in the lower set, but not so in the upper set. I could also put it that the way in which the man is holding himself: that match goes to Bookhout. In the lower set, we are seeing the exact same neuromusculoskeletal response. So, when it comes to bodily comportment and arrangement and balance (postural balance) the match goes to Young Bookhout- not Young Ruby. And it's very important because postural balance is a very deeply ingrained, subconscious habit. The depth of the eyes are totally in favor of Young Bookhout, with Bookhout having more deep-set eyes than Ruby. The lower set match much better than the upper set.
I will admit that, at a glance, the ear on the older Bookhout seems to be a better match to Young Ruby than to Young Bookhout. But, I am wondering if they moved it over, if they gave Bookhout Ruby's ear. It may have occurred to them to give Bookhout Ruby's ear- just for insurance- and it would have been very easy to do. But, overall, the match is to Young Bookhout, and by a country mile.