Surfing Waves

i just got a knew box fin for my board according to the dimensions it is ment to fit the box, however it sits about 2mm high and i cannot put the screws in is there a way i can make this fin fit ? and how would i do it ?

Try sanding down 2mm off the part of the fin that fits in the fin box. Just sand a little, try to fit it in, sand some more, and keep trying until it fits... eventually it should fit snugly.