@Waterloo I really hope this helps
When I did the timing on my 73 T140.
When your timing plug tool is in the slot in the crank, I used a small screwdriver) and the the pointer is aligned, this is TDC. I also used a pencil in the spark plug hole. As you approach the TDC you will see the pencil raise, it will be or should be at its highest point at TDC. Doing this along with the timing mark plug made this whole thing make sense to me.
1. remove your spark plugs, and raise the rear wheel.
2. rotate your wheel very slowly backwards, leave your timing tool in the plug and let it gently touch that crank journal.
3. it will fall into the next slot. This slot is the 38deg before TDC. I used small black paintbrush and drew a line on the rotor at the primary cover pointer.
4. this is now where you line up the Boyer
rotor. I found it a helpful starting point to have the magnets at like 1 o'clock and 7 o'clock positions
5. line up the little holes on the stator plate of the Boyer
. tighten it down, not worlds strongest man tight, but decently.
6. put in the plugs, and give it a fire. It should run.
7. now you do the static timing, and rotate the stator plate to then with the engine running you watch that black line you drew, and try to get it to line up with the pointer on the cover while you HOLD the rev at 4k.
if memory serves, rotating the Boyer
stator plate clockwise moves the "timing mark" counter clockwise during the static timing.