I think that 3 thousandths of difference in point gap yields ABOUT 10 degrees difference in dwell angle.
I am sure 10 degrees difference in dwell angle produces a 20 degree difference in timing. This is due to the crank revolving twice the rate of the cam.
I have a K181 on a Troy-Built tiller. I time it with a light and when it is right, the points are tighter than the book specs. I can USUALLY start it with one rope pull if I am able to finesse the choke correctly with the other hand.
The numbers I stated above may be off somewhat, but I think they are very close. If you get a light you will have plenty of adjustment room at the points to get it timed correctly.