My hands are precise to align a two 105x70 cms films in 3 seconds. Waste an film with taking notes about how did you advanced the film and your hands will be adjusted to do the same in next few films.

When I was thinking , I think Christopher is right , measure the two red centers distance and do what he says or similar.

Is 3x4.5 vertical or horizontal ? Do you need to advance 3 centimeters or other. It changes the game

Good luck , I think you bought the camera from APUG Sheffield. He sent me an excellent Nettar.