if you can see the cam decent then just adjust them when you are on the base circle, I use what your machine shop wrote, I will explain it like I tell others, "when the exhaust valve just starts to open adjust the intake valve on that same cylinder, when the intake valve just start's to close do the exhaust valve on the same cylinder" so I just rotate the motor until the exhaust valve just starts moving and then do the intake, then I rotate until the intake is all the way open and then watch until it just starts to come back up (closing) then I adjust the exhaust, your machine shop wrote to do it when it is almost closed, I don't do it that way. I have used the chart posted above and that work's also, until you get into some of the more radical cams, also if you don't have 90 degree lines on your dampner you might not get it exactly right.
