Henry, Thank you for your insight. As a follow-up question, is it possible/acceptable to leave the 2-wire system in place and just add a separate ground wire? The outlet & switch boxes are metal. I am not trying to do this the 'cheap & easy way', but wanted to look at all my options. I guess it partially depends on the condition/rating of the existing wiring (which appears to be in good shape) to determine whether it would be worth leaving in place or removing. Thanks again. Andrew