i had a plug fouling problem on a 200x ( my first one ) along time ago and it was because the owner i got it from was setting his valves correctly by aligning the "T" mark on the altinator but timing it with the same "T" mark instead of the "F" mark on the altinator ( they are very close together and hard to spot sometimes ).
if rotating the motor counter clockwise the "T" mark will show first and maybe like a half inch farther in rotation the "F" mark will show up.
john