The Stovebolt Site Forums The Parking Lot Tons 'o Fun 19.5 wheel lugs

I finally acquired 6 powder coated 19.5" wheels and 225/70 tires to replace the 3 piece 18" wheels on my 1959 38 flat bed. My truck has 1/2" lug bolts and the wheels have 5/8" bolt holes. The center hole is the correct size (4.56").

Is there a solution to the lug size difference short of drilling and replacing all the lug bolts with 5/8" ones?

The wheels did not come with mounting rings (the flat piece between the tire and lug nuts). Are these required?

Any words of wisdom are appreciated as I figure out how to use my new rolling stock.