One Inch is not a lot of variance.
If you want to, look at it this way...
First the floor is NOT perfectly flat.
Second, if you compare right to left,
you could say that one side is 1/2 inch higher than it is supposed to be,
while the opposite side is 1/2 inch lower than it is supposed to be.
Don't dwell on it.
If the steering is straight, and the car rides fine, leave it alone...
