Hi Rich,
Depending on the complexity of the model (i.e. on how many faces you need to do this), it can be easier or even worse...
After projecting the photo, exit the PM tool and go to the faces. Right click each face and make the texture unique on each. This should crop the image at the boundary of the face on one hand and make it rectangularly mapped on it on the other.
A lot of renderers have issues with matched photos and this procedure generally helps.