The blue sedan with US Government plates that chases Jacob is a 1975 Ford LTD. This was the first model year to have the style of tail lights shown in the film. According to the facts revealed at the end of the story, there should be no vehicles newer than 1971.
In the scene where Jacob and Geary are walking down the stairs, Geary is holding his briefcase with his left hand. After he says "war games in Thailand" and makes a motion with his right hand, the next shot shows that hand now holding the brief case.
Jacob opens a box containing artifacts from his past, and takes out his Doctrine Degree. He next takes out his Army Honorable Discharge, which lists him as a private 1st class. A person with a PHD (or any college degree) would by default be a commissioned officer, not a enlisted private. His conversation with his chiropractor Louis confirms that he had his PHD prior to going to Vietnam, and worked for the post office after he returned, so he could not have received his PHD after his Army Discharge.
The goof items below may give away important plot points.
During the scene where Jacob goes to a party with Jezebel, the song "Lady Marmalade" is playing in the background, which is fine if it's 1975 as we are led to believe throughout most of the movie. However, at the end we find out that all of the action happening in "present day" was a hallucination that Jacob was having in 1970-ish, therefore, there is no way that Jacob could have known that song, which came out in 1974.
The B train (that Jacob is riding) does not stop at Bergen Street and never did. However, because this takes place in Jacob's hallucination, this may be a deliberate goof made in the character Jacob's subconscious.