if you mount it inverted you don't have to chop big holes in the side of the cowl and destroy the lines of the planes
this is a very good point and the exact reason i decided to turn my engine inverted as well. the only problem i'm having is my engine was second hand and the grooves on the front of the thrust washer is worn a bit (i'm guessing from it's previous owner using an aluminum spinner) so i've got plans for a new one.