While doing the story mission where in ORR i shot the undead with a tank, i noticed my character was outside the tank AND when i aimed (with 1 & 3) my character move left or right until disconnected from the tank. This would also result the tanks cannon going as much in that direction as possible. So when i targeted left with the key one, i moved left, got disconnected from the tank and the cannon was facing to the left.
And i made a thread before, the animations considering mounting cannons and tanks are so so underdeveloped..