Just separate it at the adapter to engine block flange. If it does not want to separate the shaft is rusted into the flex plate . If that happens you will have to remove the upper gear housing and the 6 bolts that retain the adapter housing and pull the whole assembly out.
found the p/n in my manual, 11009, got one on order, obviously going to be doing alot of cleaning and detail work, on both boat and engine this week, might get a little boat time this year yet....
The pilot bearing is for the auto with a standard transmission. Just be sure to grease everything before reassembly. How does the shaft that plugged into the engine feel when turning it. This would be a good time to replace the driveshaft bellows and inspect the universal joints.
thanks Kenny, yeah, checking, cleaning and lubricating and painting everything....did seaplane maintenance for almost 30 years of a 40 year aviation career, real familiar with corrosion control