:-/ I am sorry.. I think I cannot be of help here. Maybe.......
You got another Mac capable of booting 8.5/8.6? You may could place your HD to it and try the Updater there (I guess it doesn't boot right now? does it?)
You got another Mac capable of booting 8.5/8.6? You may could place your HD to it and try the Updater there (I guess it doesn't boot right now? does it?)