East Hill: Hi. Bought the complete bike with Campy Centaur. A couple of swap outs from the LBS to make it fit better (slightly upright stem, different saddle), but that's about it.
Hoopsterky: Howdy. I too had numbness issues. When I first got the bike, I had bar ends installed so I could have more positions. Then I put some neoprene padding on them, and use padded gloves. Two things helped: 1.) getting used to riding longer distances, and 2.) switching hand positions frequently and giving my hands a good "shake out" before the numbness sets in too bad. My first year, I did a 75 mile ride on nowhere near enough training. My right hand went so numb that I had zero grip strenght...couldn't squeeze my water bottle or anything. I didn't get my hand back to normal for almost a month.
Bottom line, I think I just got too tired and was putting too much weight on my hands. The better shape I got in, the more balanced I was, which put less pressure on my hands, resulting in less numbness.
Don't let your bike hold you back. You can do centuries on a bike like yours, and laugh at anybody who tells you that it's not possible (as you pass them of course).