rosgunt

hello all, my brother in law has a '74 260z that he asked me about an electrical issue that he has developed. When he first purchased the car he had interior and exterior lights. Now nothing works, i figured bad ground so i checked all connections. they are clean. Then checked fuse panel, no power at any fuse, which leads me to believe the fusible link. when we checked that we found the rear wire lead to be broken so we made a "jump" wire for test purposes. When we installed it we got smoke and spark at terminal connection, but still no lights. I am at a loss, did i miss something, going about this the wrong way. Any help or ideas would be appreciated. thanks Dan