Don't forget, the fuel pump is run off the camshaft and could be making noisy at the sametime the valve is opening. It might be worth your time to remove it before the head
Leading up to this, I had just cleaned/refurbished the fuel pump, and suspected (hoped) that the fuel pump actuator on the cam was making the noise... So the fuel pump was the first thing that came off while I was searching for the noise. Then the valve cover... Then the oil pan... Then the side cover over the push rods...
Visually, the rise and fall of the bad one relative to the others looked the same to me... It didnt occur to me to measure them more methodically and look for a variance to small to see visually. I have been worried about this being a problem on the cam, though. Been hoping for a helping hand with more muscle than my 10 year old son to come turn the pulley on the crank slowly while I reached in through the fuel pump hole to feel the cam surface that drives that pushrod... or just to watch it from underneath if I can get a clear view, since the oil pan is off.
