If 0 remains on the display, that means the CPU is not booting. Start at the beginning - proper voltage on to the CPU board, ROM sockets good, 40 pin interboard connector, cold solder joints on the header pins (power and sound boards too).
0 - Test Passed
1 - IC13 RAM faulty
2 - IC16 RAM faulty
3 - IC17 ROM 2 faulty
4 - IC17 ROM 2 faulty
5 - IC20 ROM 1 faulty
6 - IC14 Game ROM 1 faulty
7 - IC26 Game ROM 0 faulty
8 - IC19 CMOS RAM or Memory protect circuit faulty
9 - Coin-door closed, Memory protect faulty, or IC19 CMOS RAM faulty
Newcastle, OK
