for most of the games you als can do a romfix (patch), if....you have the equipement for (e.g. empty eproms, eprom-burner station, pc, soft...).
i fixed like that my 3 wonders (midnight wonders...) back in the days. altough i needed a security board from a street fighter II' as replacement for the battery board. today, they have a lot of ways how to fix suicide boards.