This hairstyle comes in four versions:

One replacing Diana Allers' hair with the textures manually replaced.
One replacing Diana Allers' hair with a texmod.
One replacing the Custom Cute hairstyle with textures manually replaced.
One replacing the Custom Cute with a texmod.

Replacing Diana Allers' haistyle results in less clipping, but some stretching when Shepard turns her head. Replacing Custom Cute has no weird stretching but clips some when Shepard tilts her head to the side. Pick your poison.

To learn how to install .pcc files please visit this link.

There is a modding resource pack for modders or manual replacement. I claim nothing. No permission needed for anything.