Husky 562XP Timing Issue!

[Sprinter]

Years ago I had a  cast in flywheel key that disintegrated. I fixed it by filing out the remains of the key and fitted in a bit of copper wire to locate the flywheel and keep timing. Worked okay!
Then a couple of years ago it refused to start. I can't remember exactly how it came about.
Yesterday, I pulled it out again. Compression and spark okay, fuel as well. So I started worrying about timing. So, I pulled the flywheel and found the magnets off maybe a 1/4 turn at top dead center, key was still in place. Checked other running saws to see where it should be.
Ended up setting the flywheel without the key and set the timing so the magnets were just leaving the coil at TDC. Now it runs but not well.
My question is, how could this happen and how do I find the right timing spot. Runs but I don't want to ruin it.
Hopefully someone can give me a clue! 
If the saw fires when the magnets pass the iron core of the coil then my timing is about 28 degrees before TDC.

[Sprinter]

Looks like it's good. Did a low speed reset and found an 8ft cedar to rip.
Seems good as new.