mm or degrees, minutes, seconds???
These are two entirely different measurements. One for angles and the other for distance.
If you are going to use distance, you need to be certain what you are measuring from and how far out from the point of origin. The further away, the longer the distance between the true centre and where your tyre is pointing, but you may already be accurate in your settings.
If you are using distance, then it is from the centre of the wheel and the distance from it is irrelevant.