An assembly including a support plate through which passes an opening with two faces parallel to a bearing plane, a first fixing fixed against the first face, first sleeves receiving beams, and a stud with a hole having an axis, a second fixing against the second face, second sleeves receiving beams, a housing for the stud and a clamping screw screwed into the hole, with the axis at an angle (α) to the bearing plane between 10° and 80° inclusive. The assembly forms a chassis which may be fixed to a propulsion assembly and a wing of an aircraft.