I think a full movement re-enactment would be very interesting..
From the 2nd floor encounter onwards.
http://jfkassassination.net/parnell/chrono.htmLooking at the timeline above...
12:31:30 PM: LHO is confronted in the lunchroom by Patrolman Marrion Baker. The
superintendent of the building, Roy Truly, vouches for LHO, and he is released.
12:33 PM: LHO leaves the TSBD by the front door (presumed).
In 90 secs, he purchases a Coke, then walks across the 1st floor in no hurry, goes down a flight of stairs, (probably) points out the phone to a journalist, reportedly gets seen by Campbell, retreives his jacket and then pushes past the crowd at the front of the building (filled with people like BWF, who know him), alwhilst taking swigs from his Coke, as he has finished the Coke by the time he gets to the bus.