The Mount was rendered in SolidWorks for my graphics course at NC State University.
This was a particularly interesting drawing to tackle. At first I sketched the one of the side drill holes and then used circular mirror patterns to make 4 more holes each at 90 degrees to eachother. I then extruded the sketch. The angle cuts were the tricky part. I sketched in the frontal plane and made a right triangle with the proper angle needed. I then cut with that sketch to the proper width. The counter-bore hole in the middle was just a simple cut. This drawing took me 40-50 min due to having to figure out how to cut the angled plane.