Is there a trick to setting the points on a 56 Johnson 10 hp

[macawman]

With the flywheel off, I set the point cam follower block at the high point of the timing cam and set the point gap to .020. However, after I install the flywheel and torque it down, the point gaps are way off. So, I go to reset the points through the service holes on the top of the flywheel, but the timing cam is hidden under the center hub of the fly wheel so I can't tell where the high point on the cam is. Is there some trick to determining the high point with the flywheel installed?

 

[Pappy]

There is no trick and the gap should not change with flywheel installation.
As you said, points should be set at .020. I almost always see points that are way less than this. This is usually because folks use a drag method of setting them. When this is used you can always see the points arm moving and opening to accept the feeler gauge. Not the way to do it.
Look carefully and I bet this is what is happening. Set them and look at the points arm. You have to feel the gauge but the arm should not move to accept the gauge. That will be a true .020.

 

[macawman]

Thanks, Pappy.