Yeah I think I’ll be sticking them as I go but could you bond all the Karndean on to the ply before fitting the ply with the Karndean fitted into the van? Thinking it might be easier as I could just fit the Karndean with a overhang then scribe and cut around the profile of the ply or use a router to trim it to the ply.It will be quite hard to cut all pieces first as they will move while trying to set them out , I usually cut the first couple before glueing then you can measure and cut them as you go the straight cuts just need scoring with a Stanley knife then they will snap , but some of the higher price ranges like van gough are harder to work with as the are thicker ,