Spanners
Boeing have offered to develop SB for our specific installation but this would take longer - and cost more - than the STC process we're presently following.
Shore Guy
We have direct GPS feed although the installation differs slightly between aircraft batches.
Bolty
Do you know how QF accomplished the mod - presumably not an FAA STC so Boeing SB or locally-approved EO?
All involved in our situation - including the DAR - seem to be confused as to whether an STC is required under FAA Advisory Circular AC25-23 and other docs.
Anyway, many thanks for all inputs so far.
Torque.