Was able to get the tach going with the help of Dakota Digital. The standard settings would not work, regardless of if we used engine speed sensor, coil, or injector pulse, but with their help we were able to get a workaround in place. Posting it here in case it can help anyone in the future getting their early non-CAN 986/996 tach working.
Using the SGI-100BT, we tapped into the Diesel input, and selected Flywheel. The TTV flywheel I and others have used is 58 teeth, and with that info the converter was able to send an accurate signal to the tach from the engine speed sensor. Other settings were low voltage and original engine cylinder number was 6 as expected.
On to some shakedown runs ahead of end of July track day.
