within

[Fluttershy]

a unit wholly within (n)" doesn't require to have all model bases wholly within right?

is that correct?

[EMMachine]

Yeah, like @King Taloren said.

The FAQ part he meant is in the corerule FAQ page 3

Quote

Q: Sometimes a rule will specify that a model or unit needs to
be ‘wholly within’ a certain distance. What exactly does ‘wholly
within’ mean?
A: A model is wholly within a certain distance if every
part of its base is within the stated distance. A unit is
wholly within a certain distance if every part of the
bases of all of the models in the unit is within the
stated distance.
For example, a model would be wholly within 12" of the
edge of the battlefield as long as every part of its base
was 12" or less from the edge, while a unit would be
wholly within 12" of the edge of the battlefield as long
as every part of every base of the models from the unit
were 12" or less from the edge.

Blue is "within" (a part of a model has to bee in range)

Red is "wholly within" (all models have to be completly in range)

The case with the  green models is also used in the rules. This this case the rules for "Obstacles" (the particular part maked in blue)

Quote

OBSTACLES
Some terrain features are obstacles
that block attacks to targets that lie
beyond them. When this is the case,
it will be noted on the warscroll for
the terrain feature.
When a missile weapon targets an
enemy unit that has all of its models
within 1" of an obstacle, then the
target unit receives the benefit
of cover if the attacking model is
closer to the obstacle than it is to the
target unit.

Green would be in this case "all models within range not don't have to be wholly within the range"

[King Taloren]

No the red is wholly within. FAQ has stated that to be wholly within the range all parts of the models in a unit including the base must be inside the range. 

Within is only way that bases and even other models of a unit do not have to be completely inside 

[Fluttershy]

ty