@RetiredMan93231 That works for me :) Thanks to all for the input on this thread.
For further information, this is the load_safety_factor line from the Bonanza flight_model.cfg file:
load_safety_factor = 1.5 ; Flap negative load limit when down. Same dimension as gravity vector FEET/SECONDS^2
If this is correct it appears from this that the load_safety_factor line only applies when the flaps are down, which further justifies changing the negative G limits in the Piper Arrow file rather than change the load_safety_factor.