Align Face on Axis, Rotate Vertices

2 questions:

  1. How do you precisely align to a face on an axis? I have a vertex which I slide along the X-axis. I want it to snap perfectly to a face, where the face’s Y and Z coordinates are that of the vertex. Is there a script that allows this?

  2. How do you rotate a set of vertices (forming a perfect line) along the Z without losing their X coordinates?

  1. Shrinkwrap Project mode does that without manual sliding. Snap to faces on and g along axis - as soon as there is a small ring vertex has landed.
  2. Rotate not losing, what?
    Or, was it along or around; i’m lost if that was along.