You are right. It is a start/retarded. Like me in the morning.

Run advanced.
A person with a magnetic timing light, the type that closes around the spark plug wire, MAY>>MAY get enough signal thru the shielding to see the firing time.

If he can. Take the plug out and bring the piston to the top. That is TDC. Or 0 degrees of timing. Put a mark on the non-moving part of the engine as a reference point. Rotate the engine BACKWARD 90 degrees. Put another mark. That is 90 degrees BEFORE ..TDC. Rotate the motor 1/2 way back to TDC. Mark that point as 45 degrees before TDC.
Still with me ?
ALL timing light flashes HAVE TO OCCUR between 0 and about 38 degrees before TDC. No exceptions.

Rich