Find the missing digit:

0-7?787-04104-2

0x3+7+Nx3+7+8x3+7+0x3+4+1x3+0+4x3+2=0

7+Nx3+7+24+7+4+3+12+2=0

66+Nx3=0

6+Nx3=0

Nx3=0-6

Nx3=4

We need Nx3=4, 14 or 24

8x3=24

N=8