82 AUDI TDC timing mark

[DutchTouch]

Where do I find the TDC timing mark on my 82 Audi 4000  diesel?  I think the  crank may have slipped a tooth while I had the cam and injector pump locked down /pinned while installing the new timing belt.

I rotated the engine through 2 revolutions, no interference, but the motor runs like crap and smokes badly like the timing is retarded pretty far since having the head cleaned up with .006" removed, in a few passes on the end mill.

Any pictures or suggestions?

Thanks.

[Audi80]

The TDC mark is at the flywheel. There is a hole in transmission where you can see it.
Picture