Aha! So for the actual adjustment it doesnt matter, it is when you go to snug the outer nut down that you want to hold the inside securely to prevent the shaft turning. Right?So you can hold the inner nut steady while you tighten the outter nut. The way you did it there is a strong chance you can turn the shaft. Turning the shaft is bad.
I did hold the shaft with a pair of snubnose pliers to try and prevent it turning.
Another question, how far can you adjust the inner nut? I turned it till there was the slightest change in resistance and stopped, then tightened the outer nut down. The truck runs great, leaves a slight trail of smoke, but even an off-idle rev doesnt produce the thick black smoke i've seen in a few videos. (Yes I have a pyro to watch temps)