Inop fuel pump. One of the three phases shorted to ground at the pump plug.
On a 767 there is a feed-through hole on the rear spar that the wire bundle(s) passes through to get to the pump plugs.
Just up-stream (towards fuselage) we found a bundle wrapped in F4 tape. What are the odds that our problem is there???
Cutting away the tape revealed a shitty splice (wrong type also) in which the red phase wire was in contact with crimped shield splice.
No extra wire..... so we'll be pulling a new one through the hole all the way to the pump from the last known good section of the original wiring.