Late to the subject but...
I just measure the x,y offset of the label on its paper and subtract the x,y
offset of the subject matter within the image. I then use these to set the
margins in "Page Setup', assuming the image scale is correct.
Else I use the 90% OnTopic program LView32.exe to scale it.
It usually works out to: Print one on plain paper, measure the offset
required, set the margins, print on label.
John A.