Which "variation" of the SBT was proposed during the autopsy? I've never read that. From what I've read the autopsy doctors never considered the wounds on Connally. Why would they? Their job was to determine the cause of the injuries to JFK not Connally. Moreover, Humes said (the JAMA article, for example) they couldn't figure out where the bullet that entered the back went to. It wasn't until the next morning when he called Perry and learned that the trachestomy covered a wound to the throat that they concluded it had exited there.
The FBI summary report didn't have access to the autopsy report. They relied on the Sibert and O'Neill account of the autopsy, an account which was incomplete. From that the FBI concluded two shots hit JFK and a separate shot hit Connally. No SBT at all. No missed shots. Three shots, three hits.
FBI report is here: https://www.maryferrell.org/showDoc.html?docId=10402#relPageId=3&tab=toc
JAMA article is here: https://www.history-matters.com/archive/jfk/arrb/master_med_set/md22/html/Image00.htm
James Curtis Jenkins 9/23/1979 interview with David Lifton
[Part VI ? 1979: The Coffin/Body Problem], [Chapter 27 ? The Recollections of James Curtis Jenkins, et al.], [Interviewing Jenkins]
Jenkins had vivid recollections about the controversy concerning the neck trajectory. The wound at the front of the throat, throughout the autopsy, he said, was assumed to be a tracheotomy. Yet, said Jenkins, the civilians who seemed to be in charge seemed to be trying to get Humes to conclude that a bullet passed from back to front through the body. Jenkins had a clear recollection that that wasn?t possible. He remembered very clearly Humes? probing the back wound with his little finger. ?What sticks out in my mind,? Jenkins told me, ?is the fact that Commander Humes put his little finger in it, and, you know, said that . . . he could probe the bottom of it with his finger, which would mean to me [it was] very shallow.? He had another recollection. After the body was opened and the organs removed, Jenkins watched the doctors probe it again. ?I . . . I remember looking inside the chest cavity and I could see the probe . . . through the pleura [the lining of the chest cavity]. . . .?
LIFTON: Explain that to me. You could see the probe that he was putting in the wound? You could see it through the pleura?
JENKINS: You could actually see where it was making an indentation.
LIFTON: . . . an indentation on the pleura.
JENKINS: Right . . . where it was pushing the skin up. . . . There was no entry into the chest cavity . . . it would have been no way that that could have exited in the front because it was then low in the chest cavity . . . somewhere around the junction of the descending aorta [the main artery carrying blood from the heart] or the bronchus in the lungs. . . .
LIFTON: Did you hear Humes say he could feel the bottom of it with his finger?
JENKINS: Yes, I did.
I told Jenkins that Humes testified that he found a bruise atop the upper lobe of the lung, and that was the evidence for the bullet going all the way through. Jenkins told me he had no recollection of any such bruise being examined the night of the autopsy.
I was unwilling to believe that Humes made that up out of whole cloth; and, anyway, photographer Stringer told me he had photographed it.
I asked Jenkins what conclusions he had expected the au- topsy report to state based on what he saw while he was there. He said he assumed the report would have concluded that the President had been shot once in the back from behind ??and that they could not find the bullet?? ?and that the second shot, to the head, came from the front.
I asked Jenkins how he explained the autopsy report that was written. Jenkins minced no words. He said that Humes was a ?super-military type of person??? not in the sense that he was authoritarian , but that he was concerned with his next promotion and his career in general. ?He was the type of individual that would do anything anybody above him told him to do . . . my personal feeling is that he was probably directed to write the autopsy report.??
Jenkins told me he has always assumed such ? directions?? came ?from someone outside the hospital.??
I said that the chain of command was short? Humes? senior officers were Stover, C .O. of the Medical School; Galloway, C.O. of the Medical Center, and Kenney, the Surgeon General. ? And then you?re either at the Joint Chiefs of Staff or orders from the White House.?? Jenkins replied : ?I didn?t say that; you did.
It was obvious that he had given the matter some thought, and he was not comfortable discussing it.
Jenkins? statement that the ?Friday night conclusion?? regarding the neck trajectory was different from the autopsy report was not new. That was the old ? non-transit/transit conflict between the FBI report and the navy autopsy. But the statement that the doctors did not come to a firm conclusion about the head shot, that their discussions were tentative, was new. To evaluate that , and much else Jenkins said, it is necessary to make a brief digression.
[...]
[Part VII ? Synthesis], [Chapter 30 ? The X-rays and Photographs Reconsidered], [The Puzzle of the Ruler]
James Jenkins told me that during the autopsy, when the "civilians" were practically arguing with Humes, they put the idea to him that the bullet entered at the rear, exiting through the tracheotomy incision , and that that bullet went on to hit Connally.**62
[...]
**Unfortunately, Jenkins never made a written record , and so it is easy to discount his recollections by claiming he was influenced by what he later read in books and magazines. But having spoken with him, I didn?t belive that was the case. Jenkins did not follow the case and, in fact, until I spoke with him in September 1979, did not know a bullet wound at the front of the neck had been observed in Dallas. Jenkins kept referring to it as the "tracheotomy incision," and couldn?t understand why those ?civilians in the autopsy room kept claiming that a bullet exited there.