I made yet another stab at the knee socks today, and I think I'm almost there!
My last attempt moved up to the 72 cylinder. It fit around the calf, but was too baggy through the ankle and foot. This morning it occurred to me that when I put on the heel spring, the tension tightens up. What if I put the spring on when I got to the ankle, and just left it on until I was done with the foot? Off to the sock knitting machine I went!
Lo and behold, it worked. Leaving the heel spring on tightens the tension from 13 rows per inch to 15 rows per inch, and brings in the circumference. I went ahead and made the matching sock to the one in the picture, and I'm wearing them now. They are comfortable, and the ankle and foot fit beautifully. The leg of the sock fits nicely over the calf. However, the leg of the sock is scrunching down after several hours of wear. I think I need to make the cuff bigger, and perhaps a bit tighter. And I need to lengthen the leg so the top of the sock hits well above the biggest part of the calf. I think those changes will keep the body of the sock where it belongs.