I attempted to chip mine last week but failed miserably. Found a guy on the net, consoleworkshop.co.uk. Have sent my Wii to him and he said he has repaired it and fitted a new chip as I damaged the original. Just waiting for him to send it back. Fast and friendly service with excellent e-mail comms. Did the work, tested it and gave me a quote. Told me he would put it back the way it was if I didn't want to go ahead with it. Total cost, £75.00 for the repairs and the new chip.
Foseco