Timing?

[andelund@online.no (Anders Lunde)]

I have a question regarding timing advance on my '72 Fastback. Its a
stock engine without FI. 
In just a couple of weeks it has stopped running at idle speed. The
only way to drive is to maintain a fairly high rpm. Even then it
vibrates very much. The only time it will run smooth, is when I apply
full throttle. I suspect this to be the timing that has become all
wrong. 
The question is how many degrees BTDC is recommended for my engine.
And where is the hole for reading the advance (using the timing lamp).
I know it is printed in the workshop books, and I have ordered both
Haleys and Bentleys editions. The problem is that I have to adjust the
timing this weekend, and my books won't arrive until next week. :-(

Tanks,
Anders Lunde