Tear into it, or bolt in and go???

Assuming this is a hydraulic lifter, to see if your intake lifters are bled down.
1. Pull valve covers.
2. Remove spark plugs (makes it easier to turn the motor over by hand)
3. pick a cylinder
4. Turn motor over by hand with breaker bar and socket until the exhaust valve starts to open.
5. With your thumb, press the pushrod side of rocker arm and see if it moves down.
6. Repeat