Yamaha 50 HP Lower Unit removal

[Birddog4]

I have a 50hp Yamaha P50TRLO and I can't get the lower unit off. I removed the four side bolts and the bolt under the tab and the unit slides down about 3/4" but won't go any further. Is the gear shift linkage splined ?? Do I need to take the splice/union type connector loose? Any advise would be appreciated.

[boats.net]

The shift shaft has a union nut that will need to be unscrewed enough to separate shafts, it's located in front of mid housing just above motor mounts.