The measurements I have for the L31 Cam Position Sensor Flag is 175 degrees "Flag in Sensor" and 185 degrees "Flag out of Sensor".

My daily driver has a L31 engine with an aftermarket 24x Coil-on-Plug Conversion, using the original L31 distributor Cam Position Sensor.

Sensors will trigger on Leading Edge / Trailing Edge of the trigger wheel or sensor flag. The center line of the sensor is the critical alignment point for the trigger wheel or sensor flag.

GEN III computers have a CASE Learn Procedure for "Timing", mostly for production tolerance reasons. GEN III computers will "Assume" near perfect alignment of the CKP / CMP sensors, because that's the methodology of mass production.

It can be a challenging question: is success re-engineering the factory mass production methodology, or reverse engineering the factory mass production methodology. Either method will yield success, with measurements, alignments, and parts fabrication as good as the factory mass production tolerances.

dave w