I agree with this. ^^^^^^ Although, you can fire it up long enough for this: Start the engine with the cover off. Obviously you know what side the noise is on. With it idling, take your thumb and press HARD on each rocker on the pushrod side. When you get to the one where the noise goes away or gets quieter, there's your boy. Should take less than 30 seconds. Then you'll know which one to look at.
One last thing, IMO that's too much cam for stock rockers. It's been done, but the stock rockers really don't like much over a stock lift cam. I bet it's a rocker arm. I hope it is. That would be an easy fix. With new adjustable rockers. lol
