I worked at Boeing Wichita (which is no more), and an engineer told me that the B-52 was getting heavier over time because the old wires weren't removed for avionics upgrades. Of course, they were always trying to put one over on me as a newbie (I worked on avionics S/W in Ada for the tankers).

He also said a big problem was the expense of doing a modern engine upgrade. Anyone know if they ever re-engined it? Was he joking again?

Having one of these fly over my apartment on Rock Rd. was a dish rattler--I used to see B-2s every once in a while too (fairly loud too, IIRC).