I'm wanting some kind of radius on all the corners so I decided on these two sizes. I've used sockets for this kind of thing many times before and they work great.
 

Using my belt sander I just sand to the line which goes very fast and then finish sand by hand afterwards.
 

I did a search for "clip board clips" and bought three different kinds: nickel, brass and antique brass plated. They have holes on each end for fasteners.
 

The brass screws I had were 1/2" long but I need them to be a little shorter so I used my belt sander to shorten them.
 

I'm laying out the holes here and by turning the clip around I'm able to achieve the exact distance from the edge that I need.
 

I used my combination square to find the center. Then I used a pencil to layout the holes by drawing a circle where the screws go.
 

 Here you can see the screw locations.
 

I centered the drill over the hole and drilled them all. Very simple, quick and worked great.
 

I sanded the screws to .320" long which was just shy of the hole depth. This left me some room so I didn't bottom out the screws.
 

The next day I took all the clips off and applied a semi-gloss finish to all the surfaces. In this picture things look good but I had some trouble. I started with the bottom surface and applied two coats a clear. Once that was finished I wondered if I would have enough for the other side. And I'd been dealing with little chunks of stuff that had settled at the bottom of the can all along. Sure I sanded between coats but this was another level of ugly.

I ended up with enough material for the other side but the surface looked like I used an air hose to clean the floor while I was brushing it on. Not my best work that's for sure. I again used some 400 grit paper between coats and again the following day, which removed most of the bad spots but you could also see scratches from the sandpaper. A few days later I applied some mineral oil to both sides and that helped. After wiping off the excess oil I could only shake my head from side to side because I wasn't happy with them.

I could have ordered more Zarr semi-gloss but I didn't have another project that would warrant buying it so I'm going to leave them as is.