Try the next one with the key parallel to the centerline of the crankshaft and see what happens. It’s a bit tricky to do but the key must be fully seated in its groove and the cam should slide easily over it. You may have to remove the mag plate to seat the key properly. After reseating the key, remove the cam and make sure the flywheel is bottoming out on its taper to. It may take more than one attempt but that key has to be right. If the key has any burrs on it, they can be removed by rubbing the key back and forth on a fine file. If the key is loose in its groove, it can be tightened up by lightly dimpling its side with a center punch.
When the flywheel is ready to go on, the crankshaft must be turned so the high point of the cam is midway between the rubbing blocks on the points. Failure to do this will result in damaging the points as the cam will be held up by the spring and the cam will catch one of the rubbing blocks. If you’re lucky, the cam will be just high enough so the rubbing blocks and oiling wick are still in contact with the side of the cam. When the flywheel and cam slide down easily, torquing the flywheel nut 40-45 ft lbs will seal the deal.
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