My Boeing Fleet had a solution published back in 2000 (BCS381). I don't have access anymore but it should still be there for those that have. The preamble states
We are aware that other operators have developed their own procedures for refueling and for loading/off loading passengers and baggage with an engine running. These procedures were developed to support operations at airports which lack external electrical power or engine ground start equipment when an airplane arrived with an inoperative APU. Although such a procedure can be conducted with reasonable safety, the Boeing position is that it may only be used in exceptional and temporary circumstances and with qualified and well briefed flight crew, cabin staff and maintenance/ground service personnel. This would be considered a non-routine emergency procedure as defined in FAA advisory circular 150/5230-4 and would not be hazardous provided the following procedures and precautions, in addition to standard precautions used during refueling operations, are followed.
and continues with a number of conditions concluding with
The proceeding comments generally apply to all Boeing airplanes.
I am not going to post the full details here. Those that need it can get it from Boeing.