Purchased a 2000 - 763 with 850hrs that had not been run in a year and a half that had no power to key switch or cab . I thought i found the electrical problem . i changed the main 100amp fuse at the rear (corroded) & +ve battery cable and battery .Trying to start it but no lights in the cab panels ,nothing from the ignition swith so i went to check the fuses & found a 25 A fuse for the computer blown so i replaced it .As soon as i installed it smoke came out of the computer box ( 4 connector box ) so removed the fuse before it blew but to late . Wondering if the main there is any common harness problems .as far as the cab wondering about the grounds as nothing works .Any ideas