The normal procedure is to run tests first to see if is doable in he first place, such as did the subject use a hand-mirror to stick out the window at some point, for instance. After all, lots of ladies to powder their noses and misplace their hand mirrors.
Hilarious... so now, you've got Oswald using a hand-mirror to find out who was on the sidewalk, just minutes before the motorcade arrived? Get help, please....
stuck his head and torso out
_No torso required. Just head and neck.
Torso needed later for when Oswald gets what he deserved.
Have it your way. Show me the evidence that Oswald or anybody else stuck his head and neck (you've clearly never been to the TSBD) out of the 6th floor window of the TSBD, just minutes before the motorcade arrived. Go on then....
Meantime
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The ledge barely clears the building. No peering-down issue there.
Comedy gold and utter stupidity combined. He shows a video which proves that from the 6th floor window you can only see the sidewalk at the other side of Elm street and not the one directly in front of the TSBD. Great stuff..... 
So what's the problem?
Other than that you are a complete idiot? Nothing much... you've proven my point. You can not show that anybody on the 6th floor could have seen a person standing on the sidewalk next to the building.
I forgot for a moment who I am talking to
_YOU don't talk TO anybody. You talk AT them
Nah, I will talk to anybody who is capable of having a normal reasoned conversation. I only talk at people who are beyond help.
Other images from the same video show views that are taken too far away from the window to be able to lean the camera over the edge
As for the images I posted, they are samples (showing sizes, angles) I would post to a skilled photographer.
If I was there, I would whip out my iPhone, lean over the edge, and do it myself.
Thanks so much for your always-useful input.