After a loud valve train knock I found the #6 intake rocker very loose. I bought the tool and despite using all of the recommended techniques (hard, rapid, air tool) my pushrod never launched out of the engine. The pushrod did bounce, sometimes pretty high, depending how hard I hit the tool. The tool now has a round mark on the bottom indicating the lifter is in the correct orientation. I eventually realized the pushrod was sitting higher. I attempted the lifter re-lock technique but didn't notice any movement or click into place. The pushrod does have a metal against metal feel and sound. I placed the rocker back on and turned the motor over several times. The rocker seems fine now like all of the others. Without the pushrod launch, or confirmation the lifter's locked, I am a little nervous about putting the engine back together and having it fail again. I will do the VLOM modification. Anyone had anything similar happen? Is there anything else I can check before assembly?