Walt, sorry about my absence on this topic! I've been overcome by events for a few days!
As usual, Martin has given sound advice! The reason I talked about equal water/meat weights is to keep it simple. Although I know the combined mass is what's important (like Martin said), I just find using equal amounts works better for me. Either way is correct!
Now, as far as holding that meat for a week? Not sure I would do that. Personally, I would probably remove it from the brine and vacuum seal it, for that length of time. Martin may say otherwise...not sure. It might be fine, sitting in the brine for a week, but I don't know the answer to that.