The hours denoted on this element are well in excess of one day as after construction two trips had to be made to Philip Cronje (from Bundu Aviation) to assist with the solid riveting of the main spar.
The end product is significantly stronger than the original and this is also reflected in the weight increase with this portion of the upgrade.
In short the two flanges which attach to the cabin floor were strengthened, the top flanges of the spar were also strengthened and vertical extrusions (8 in total in excess of the original design).
