Personally I find this comment interesting.....
"...due to an inadequate design for wiring bundles on the aircraft. The Air Force requires redundancies and “safe separation” between some wiring components in the militarized 767, and the design fell short, prompting an extensive redesign and months-long delay to the first flight of the tanker......"
An indication (the "safe separation" part) that using a proven civil design for military use isn't always that simple? I don't know if this was an issue in the case of the P-8, but maybe the USN and USAF have different approaches?