How do you remove the flywheel to get at the coil on a ts350 stihl saw

The official way to remove it is an M10x1 'Knock-off-tool' right hand threads. A 2 or 3 jawed puller will not remove the flywheel, and guaranteed damage will occur. Flywheels and crankshafts have a tapered design, so when installed with a nut, the taper tightens as the nut is tightened.
OK, you probably do not have one of those on your work bench, so lets make one or something like it.
1) remove spark plug,
2) insert a 12" piece of recoil rope (use about 6 or 8 inches) into the plug hole.
3) rotate the flywheel counter clockwise until the rope has bunched itself into the top of the cylinder, stopping the piston before 'top-dead-center'
*note: this would act as a replacement for a 'piston stop'. The rope is soft, so no damage to piston or cylinder will occur. If the rope gets caught on a cylinder port, you can back up the rotation, pull the rope out, and retry inserting the rope.
4) After removing the original flywheel nut (right hand threads, so righty-tighty, lefty-loosy)
purchase two M10 nuts, thread them onto the crankshaft (but not against the flywheel) so that the end of the crankshaft is not above the last nut.
5) turn the saw over to position the flywheel up, with a medium weight ball-pean hammer, strike the top nut with a good sharp wrap.
**note: Do NOT hit at an angle, use a square, straight down strike. Do NOT strike the end of the crankshaft. 2 strikes should do it, grasp the flywheel to check to see if it has loosened.
6) When reinstalling the flywheel and nut, tighten with the same force as when removing. 20 ft.lb. is the official torgue.

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