Amy Joyce asked me my opinion of this picture, whether it is really Lovelady.
It's from this footage, but up by Jack McFile.
We know that he did take police up to the 6th floor, and we have no reason to doubt it. And I'm satisfied, based the little that we can see, that that is him, that it is consistent with his known features. But, I told Amy that I would never claim 100% certainty due to the blurriness of the image. Notice how stocky and burly he looks with that thick neck. Lovelady slimmed down a lot afterwards and was his thinnest in 1976 when Bob Groden photographed him. We know his weight in February 1964 was 170 pounds, and that's because the FBI weighed him. And we know his weight when Groden photographed him was 145, and that is a substantial amount of weight loss. Notice the high round collar of his t-shirt in contrast to Doorway Man's which was sunken and crudely v-shaped. There is no way that that guy, Billy Lovelady, was the Doorway Man.