I really disagree about the interval about 150K being the time for the timing chain change on the 119. The problem is that the chain is NOT the problem. It is the upper guides. My 119 motor (119.960) was only 5 degrees BTDC off before the change, yet both upper rails were disintegrated to hell, the chain under the left intake bank was riding on the slide pin! Therefore, engine timing alone can't tell one squat on the DOHC motors in my opinion.
I would pull valve covers and examine the upper slide rails. 100K-120K is the time for the chain, rails, and tensioner. Note the post on using only a factory tensioner for the job. BTW, the new tensioners no longer have an oil check feed on it. It's completely blocked off from the factory! Therefore, the tensioner is always under tension and thus, so is the slide rail and the chain. Great idea. Too bad it took 5 revisions before they got it right. Insist on new stock chain and tensioner when replacing them. The latest chain has a different lock on it as well.
1989 560SEC with engine 119.960 5.0L/32V DOHC