Unable to draw in perspective view after set ortho to such..to be expected?

Hi,
Desperately trying to get a view to match the perspective photo, I can draw in on the photo to map features onto my vehicle., so trying this.
establish camera position and target by doing sight lines in top view, then set up a 168cm tall cone for camera location with top = camera, and another shape for target.
create line between tops of these two for picture middle line and one line perp to this at camera cone.
create cplane to these two lines, origin at camera cone, perspective view shows view matching photo.
use Ortho view (back) in which I can draw but vehicle is not looking perspective and fails to match photo, and right click and select perspective as opposed to parallel in viewport properties.

CAD work now matches photo,

however any attempt to then trace over photo fails, lines unable to be drawn.

Steve