Chain post

I've started getting a repetitive clicking sound the engine of my 380sl , particularly when the engine is cold, and I haven't been able find out where it was coming from with a stethoscope. So, I decided to check the timing chain stretch by rotating the engine until the mark on the passenger side (right) cam lined up with the mark on that cam tower, and the mark on the driver's side cam to lined up a hair-off with the mark on that cam tower, as I believe it's supposed to.

However, I was surprised to find that the harmonic balancer was at app. 10 degrees when, IIRC, it should have been at zero, especially because I replaced the double chain less than 100k miles ago, and I change the oil every 3K miles

So, before I change the chain again, I was wondering if:

(1) My having removed the tensioner before I rotated the engine and checked the stretch could have had anything to do with the chain being 10 degrees off,
(2) It's possible that the IWIS chain I used somehow stretched more than an OE chain would have; and if
(3) Anybody here has ever used a chain made by SWS.
Thanks very much in advance for the quick responses, since my car will be sitting in my garage until I am confident that I can fix it properly.

__________________
Bill
1981 380sl