Parking on uneven ground will affect the door alignment. In fact, that's why the door guides were added. You should never try to do any door adjustments unless the car is on flat, level ground. If your doors are hitting the screws in the rear you *could* try moving the doors forward. A big deal and not always possible especially if you have an early car. You could try grinding the heads down on the screws or removing any washers (if there are any) under the screws. Often when the doors are not aligned properly they got "tweaked" meaning they got twisted and the welds and glue inside the door are no longer holding it rigid. An experienced tech can tell by opening the door all the way, grasping the bottom edge and twisting it. If it feels "floppy" the door was tweaked or twisted to the point that it is not as rigid as it should be. Try closing the door by pushing it down by the rub strip in the middle of the door (not near the rear). Do it slowly and notice if it still hits the screws. If it doesn't hit the screws that way but does when you close it by pushing it down near the rear of the door it is probably bent. If you have an early car and it hits the screws, often there is no good fix. Find screws with a smaller head.