OK! OK! I started the opening in the top with a 1/2 in. drill, but I just put the calipers on it and found that I had widened it to 17/32" when hollowing.
The main (hollow) body is only 2 3/16" in diameter. The picture above shows on my 22" monitor just a little larger than actual size.
It was hollowed with the Ellsworth-type tools I posted a picture of on the message board.
