When Murdock is rallying his troupes, he addresses one as "Gunnery Sergeant, United States Air Force". Gunnery sergeant (GySgt) is the seventh enlisted rank in the United States Marine Corps, not Air Force.
When Hannibal first jumps on the digger its a Ford 555 then when the digger makes its way onto the main road its a Ford 545.
In the alley you see Col. Decker wearing an octagon-shaped Marine Corps Cap when his uniform says U.S. Army.
When Face is scamming the building, he claims it was designed by an architect "before his untimely demise in the mid-19th century." Murdock then says that the architect was hit by a streetcar in 1948, which would be the 20th century.