I forgot to mention about how well the Tektro Alloy Brake Cable Triangle work with the Dia Compe brake double-ended straddle wire.

They come in both black and silver. You can slide the straddle wire in from the top after removing the pinch bolt first. It comes with little tiny fixing screws that keep the straddle wire from sliding either way but I didn't use them, opting instead to let it "float" rather than be fixed in place. I had originally wanted to use the VO Grand Cru pulley-style straddle wire hanger but they are not making/importing them at the moment so I opted for the Tektro instead. Those cheesy stamped old-school wire hangers never impressed me and always made center-pulls look cheap and cruddy. They look so flimsy, and aren't wide enough IMHO to get a good lever pull ratio.

I liked the look of the Paul Moon Unit straddle cable carriers but they were a bit too pricey for my blood (as are all things Paul.) The Tektro's were <$7 each with shipping from Amazon and look/work great.