Here I am using a carbide tool to machine the part to size.

The part is made of aluminum. Due to that, a good surface finish on the part is easier to attain. The General diameter of the part is 2.5in

The part looked like this when the lathe work was finished

For the milling process, I used the center hole as a reference for the mill's origin point. Then I calculated the coordinates for the holes circulating the outside. I used a 3/16in drill for the guide holes and finalized with the 17/64in drill

The set screw thread was made with a no. 8 drill to tap an 8-32 UNC-2B thread.