Further Improved MK4 Fan Duct

@JuanPuchol_41170's duct is a great upgrade to the Mk4's fan setup; but I was having a hard time printing it without a gap showing up in the one corner (see close up).  So, this is just a mild remix that adds some material in the corner where retraction settings and slicer/printer performance were leaving a gap in the finished part.  Maybe this can be incorporated into the 6.5 or later version of the part.  No other changes to the original model.

Happy Printing!

I just added a little material in the area shown in the picture to give the corner of the model a little more strength and ability to handle the retractions better.  The red circle shows the original sliced model, and the one circled in green shows the remixed version.

Maybe this can be incorporated into the 6.5 or later version of the part.