I had the same situation.

I started out with a loud clatter, but no obviously loose rockers and one easy-to-compress ball stud. I did Herr Fuch's finger check and found four with problems. Replaced all ball studs and all worn pads. The clatter went away, and I ended up with several 'tickers.' Did the adjustment with the guage, replacing four 5.1's with 5.45's. Now I think the valves are quiet, but I have some chain noise.

IMHO, you really can't tell from bench testing whether you will get noise when the engine is running. If you have noise, and you cannot find a clear indication of the problem, then I would do all the ball studs, check the condition of the pads, and check the preload with the guage and adjust as needed.

In your case, I would try replacing the two you found collapsed, check all pads for wear, and do the preload check with the guage.

__________________
Chuck Taylor
Falls Church VA
'66 200, '66 230SL, '96 SL500. Sold: '81 380SL, '86 300E, '72 250C, '95 C220, 3 '84 280SL's '90 420SEL, '72 280SE, '73 280C, '78 280SE, '70 280SL, '77 450SL, '85 380SL, '87 560SL, '85 380SL, '72 350SL, '96 S500 Coupe