The last American combat marine units left Vietnam in July 1971 as a part of the American withdrawal of troops. Curtis only went home to the Bronx in 1973 after roughly 4 years of service. If Curtis remained in the marines after July 1971, as depicted in the movie, it wasn't as an active combat marine in Vietnam.
The armored car that was blown up in the 1973 scenes was an International Harvester "S- series" Medium Duty Conventional truck. So was the prison bus in 1974. International Harvester Company did not manufacture these types of trucks until 1978.
When Cutty stands over Anthony and holds a pistol to his head, the hammer isn't cocked. Cutty had just drawn the semi-automatic pistol from beneath his jacket and racked the slide on his way down the stairs to confront Anthony, so the pistol's hammer should have been cocked at this point.
Cowboy and Anthony are shooting pool. Cowboy leans over the table to shoot and the 2-ball is clearly sitting in front of the side pocket. After Cowboy misses his shot, the view widens and the 2-ball is seen rolling to the middle of the table.
In the scene where Larenz is playing pool with Cowboy, Larenz is leaning on the table and cowboy yells at him to get off the table, there is a large white sheet of Cardboard laying in the middle of the table. When the shot changes angle to the view from the distance the sheet is gone. This sheet of cardboard would make it very hard to play a game of pool.
At the bank doors on the dock.
The soundtrack implies metal doors being unlocked and opened/closed.
The door opens and you can see that there are no bolts. It has a deadbolt but nothing on the door edge suggesting an opening.
At the top edge of the door it looks almost wood like.
The door did not even lock or have a doorknob channel.
When Jose blows up the armored car with the ordinance, the back of the truck raises up in the air and falls back down on top of a heavy metal pole revealing that the pole is what caused the armored car to jump up into the air when it shot out of the bottom of the truck and not the explosion.