The wing center needs to support only
the weight of the fuselage. Test the wing
center with the weight of the fuselage times
the number of G's.

Support the wing on a saddle where the
fuselage would mount and spread weights
over the wing in the fashion that the air would
push while lifting the plane.

Each side of the wing can be tested for its
ability to support the weight of the engines.

Support the wing by its engine mount and
spread weights over that side in the same manner.
Use weights totaling the engine weight times the
number of G's. This will test the ability of the
wing, nacelle and engine mount to carry the
weight of the engine, though it doesn't factor
in the engine's thrust.

Jenny