Paragon Transmission 'stuck' in forward

[dwkfym]

I recently delivered a new-to-me P365 back closer to my home waters in the Chesapeake bay.  We had a 150nm offshore passage down the jersey coast.  About 110nm of that was under motor-sail. 

During the cruise, among other things, the transmission stopped getting out of foward.  No neutral or reverse.  Full range of motion at the pedestal lever.  The shifter linkage arm at the transmission was moving when the pedestal lever was moving.  I don't think the clamp at the shifter nub is slipping. 

I am 2 hours away from the boat and I'm unable to go check it, but what are some places that I can start looking to diagnose the issue?  Is there a manual with adjustment procedures?  I don't have the model number off the top of my head, but it appears to be a SOAD transmission.  Sorry for the low-res pic and thank you in advance. 

[SVJourney]

Here's the link for the manual but it  isn't a very good one:  https://pearson365.com/forum/index.php?topic=1938.0

Just 4 bolts to remove the trans cover on top.  Check for shift fork movement inside.  Ensure good oil level  Prolly not an adjustment issue I don't think, but here's another thread with adjustment procedure: https://pearson365.com/forum/index.php?topic=2105.msg10886#msg10886

Good luck!