Signs of a Collapsed Lifter or Burnt Valve?

[savatreatabvr]

In my previous threads I explained again the condition of my mid '70's Chevy c20 454 and got great advise. This time I decided to hook up my vacuum gauge to see what it said. I'm leaning towards it being a burnt valve because the vacuum needle isn't perfectly steady and the lifters aren't making noise, am I right?

[Mv7fd]

To check for a bad lifter either cut the tops out or remove the valve cover and make sure all your rockers are moving properly that's how I found out that I had a bad lifter then found out I had a rounded can lobe

[Bigstevex4]

Do a leak down test check valves. or compression if bad enough.