When coupling a tractor to a semi-trailer, at what height should the trailer nose be relative to the center of the fifth wheel?

1. Significantly higher, so the tractor does not touch the trailer nose plate
2. Slightly lower than the center of the fifth wheel, so the tractor lifts the trailer slightly
3. Exactly three inches higher than the highest point of the tractor cab
4. At any height, because the fifth wheel self-adjusts during the backing process