[350TSS]

Today was mostly spent measuring so that I could ensure that the air gap to the Hall effect ignition triggers/sensors was 0.7mm and not 5.2mm.
The problem was finding a constant datum; the front face of the rotor containing the magnets was a good place to start, but the problem was that the 3 bolts that hold the sensor plate have origins in different planes. I tried measuring to the base of the threaded holes and there was about a 1.5mm difference across the 3 bolts. Also measuring to the base of a blind hole resulted in 3 different answers on the same hole, probably thread swarf from 25 years ago when it was made. Every measurement was taken at least 3 times, obviously rogue answers were discounted and the three closest were averaged. Even so the range was up to 0.25mm.
I worked out that the outer face of the 3D printed part had to be level with the outer face of the rotor retaining boss and at that point the air gap would be 0.65mm (close enough for me).
The 3D printed part that holds the sensors has three hollow legs that aligned with the three belt cover retaining bolt holes.
With some trepidation I attacked each of these with a file until the legs were the calculated correct length so that the front face of the part was flush with the rotor retaining boss.
I checked the result with plasticine and it looks about correct.
I then turned it over on the starter and it definitely isn't touching, BUT I still do not have any sparks at the plugs. I swapped the coil leads over and still no joy.
I did notice that the rev counter was not registering when the engine turned over so tomorrow I will disconnect the rev counter lead in case that is causing the issue. (I still have 12v on both sides of the coils with the ignition ON and the run switch ON).
If the rev counter lead is not the culprit and personally I doubt it then the loom will have to come apart to check the power leads to the sensors and the Ignitech unit. Fingers crossed it is the rev counter lead.