A system and method for mounting a component to an internal web of a wind turbine blade includes, at a first mounting location on the internal web, at least one through-hole defined through the internal web. A bushing is located within the through-hole and is encased within an adhesive applied between the bushing and a wall of the through-hole. A plate is attached to each of the opposite panels of the internal web at the mounting location against an end face of the bushing, with each plate having a hole therein that is aligned with the through-hole. For mounting the component at the mounting location, a bolt is passed completely through the plates and bushing for attachment of a frame of the component to one of the plates.