This link will give you instructions on how to check timing stretch:
http://skinnerbox.steaky.org/Service/W123/w123CD2/Program/Engine/617/05-215.pdf
As you can see you need to get the cam code to do this method.
This one shows how to adjust valve clearance:
http://skinnerbox.steaky.org/Service/W123/w123CD2/Program/Engine/617/05-210.pdf
You do not need the special wrenches. I use 2 regular 14mm wrenches and they work fine.
What you can do if you don't have a dial indicator is adjust your valve clearance and while you have the valve cover off take a few measurements on the cam tower marks.
This will give you a rough idea of where your at.
Then when you get a dial indicator you can get a true reading on the chain.
Also there are earlier and later versions of the chain rails. The earlier versions are white. The later versions are black.
If you have black guides chances are they were at some time replaced.
I'm not saying that if their black they were replaced I'm just saying that maybe they were.
You may want to bookmark that Steaky site.
Do a search on Timing Chain for more info.
Danny