The Boeing wiring diagrams are an absolute joy, especially on the later model A/C. Using equipment designators from the wire prints to get part numbers has saved me many hours of searching through the IPC's. Then you have the wire lists, ground lists, splice lists, connector lists, and all the other good to know stuff in chapter 91. It seems Boeing goes out of their way to make the lives of R&E types easier, and I appreciate that. A luxury I didn't have when working on Lockheed products in the Military!