You know, I have been adjusting valves in cars and trucks for the better part of my life and you can adjust any valve as long as it's on the back side of the cam... or not tight. No need to identify TDC and mark a pully or push the pin in. As a side note, I went to Cummins west and I watched as a guy adjusted a 5. 9 motor. He just adjusted them on the back side and when I asked if he used the barring tool and the pin he just laughed. He said the barring tool is too hard to use for valve adjustment and even if you are able to find TDC, 1/2 the time the pin won't engage. He says to use the alt nut and run the motor backwards until the valve is on the backside of the cam lobe and adjust it. Move on to the next valve and do the same. He did say, however, that the motor needs to be relativly cool. I asked how cool and he said 4 hours cool.
-Paul R. Haller-