OK. I re-loosened all 4 bolts at least 1/4". I started and popped it in gear for a second. The coupler is loose. In fact it was so far back the gap was too big for the feeler gauge. I couldn't pull it closer reaching in there. I got out, went around and pushed in at the prop to close up the gap. Trying to figure out how to reach around to measure all 4 points because rotating the shaft just causes the gap to open back up as the coupler slides apart. I can't pull it in with just my fingers on the coupler.