Please help elecrtical problems

[EnixXI]

Hey wats up, im new to this forum and i was hoping someone could help me.... I just finished dropping a kaaz lsd into my '96 240sx. I went to go start the car and I had no power anywhere.... when i turned the key nothing electronic got any power. I tried jumping it but when i connected the jumper cables my terminals started smoking. I disconnected the terminal from my battery and wired another battery in and the positive terminal started smoking as soon as it was hooked up. Even when it was smoking there was still no power anywhere.... I think its some sort of short but I dont want to have to rip out the whole engine wiring harness if possible.... does anyone know of similar problems??