For major items of structure, the loads are a function of the overall aero forces, or the load factor times the weight (mass). So the loads on the wing structure, for example, are similar at 50,000 lbs and 3g as at 75,000lbs and 2g. But a piece of fixed equipment - say a radio - sees a load on its fittings dependent on its own mass and the g. So the highest loads on things like brackets for radios occurs at min weight, as that's whee the highest g is created.
Of course, it's never that simple.