A system, device and method of framing an opening, such as a window, in a clad façade 12 structure to align the window units 22 to be positioned adjustably so that the exterior sight lines align the windows without custom fabrication of the clad façade. This allows irregular variations in the original building structure to be eliminated by a perfectly aligned façade. A frame 20 has wide flanges 40 to allow the defined inner box frame area 34 to be positioned and then the frame can be shimmed to that position. Sections of frame 20 are joined by an angled member 54 with flat portion which are received in slots 56 in frame sections at their edges.