
Hypothetical shot onto Houston Street. I suppose the rifle could be moved forward a few more inches\if the shooter found it necessary. The shooter could have to be couched or on one knee, not sitting. The bottom inset picture in the image above is not from street level.

Thanks for posting that visual aid. If the box leaning on the window sill was in that position when the JFK Limo passed by, it would serve No Purpose other than as a rifle rest. That box certainly is Not bracing the stack of boxes positioned behind it, as the box is not jammed between the stack of boxes and the window sill. A possible legit shooter in that window would also then mandate a Spotter. If this tandem were prepared to alternate between the roles of Shooter and Spotter, 1 shooter would then use that box on the window ledge as a rifle rest for a shot(s) down Houston St. If a shot or shots down Houston St. was nixed for some reason, then the Spotter for the Houston St shooter morphs into a shooter and uses the stacked boxes as his rifle rest for a shot(s) down Elm St. This possible 2 different shooters would most likely involve 2 different rifles. (1) Carcano + (1) Mauser.