Hey Jay,
Yes, ball-ball with the T&D. Talking to Barry today, he mentioned the method that he liked to use is to back up the adjuster and take the measurement. He said T&D likes to have their adjuster about in the middle and only turned + or - one turn. Which seems to be what I recall reading in their instructions. Barry recommended one turn preload on the hydraulic lifter. So, the one turn preload will put the rocker adjuster in the optimal position.
Today I took an old FT pushrod which was ball-ball cut about 2 inches out of the middle. Then threaded the ends about 1 1/2 inches on both ends. On the lathe, I turned down a piece of 3/4" to about 1/2", then drilled and tapped the tube. It came out o-k.
The cam is on the base circle and the rocker shaft was tightened down. I put the adjustable pushrod in and lengthened it until there was zero lash. I would then remove the rocker assembly and remove the adjustable pushrod without disturbing it's adjustment. Measured it with the dial caliper and twice came up with 8.592". I think this is the first time I have ever measured for custom length pushrods which is why I am not totally confident in the measurement, even though the proceedure is strait forward. I guess I am not confident because my measurement differs from the recomendation from a reputable source.
The adjustable pushrod tool was the first project on a "new to me" lathe: 1940 Pratt & Whitney model B 12x30.