checking compression on diesel 6.0l f350 2006

compression tester: https://amzn.to/3Bu8g2Q 2006 f350 6.0l diesel not running at all compression roughly 360 , 340 , 400 , 300 . Heads may be compromised from a recent overheating. Performed this test on the drivers side first due to the ease and accessibility. This engine is more than likely bad but may perform few other checks before pulling it .