Since the engine sits quite close to the firewall, it may be difficult to read the timing mark on the balancer when timing the engine. One way to make this simpler is to:
1. Set the engine crank to TDC.
2. Make a mark on the flywheel and a matching mark on the Porsche trans casing. The Porsche transaxle has a vent hole where it mates to the adapter plate. You can see the flywheel from this point.
3. The best way to mark is to paint a 1 inch square on the flywheel rim with black paint. Then paint a thin yellow line for the timing mark. You don't want to punch a line on the flywheel since it may put it out of balance. But you can punch a mark on the trans casing.

This way it should be easier to see the timing mark from the rear of the engine. It is best to use an engine analyzer instead of a standard timing light. An analyzer allows you to adjust the strobe to match the engine RPM in degrees advance. When the timing mark matches the trans mark, read the dial to get the advance. It is also better to set the timing before the body gets permanently mounted so that you can read the timing on the balancer before it becomes impossible to do so.