I have a lower unit that I am trying to get working to put on a 57 Elgin 7.5 with neutral shift.  The shift cable is locked up. I’ve soaked PB blaster for days but no luck.  I don’t know exactly how it is supposed to work so I’m hesitant to force it in a way that isn’t correct. Attached some pics so maybe someone could explain what I should do to free it up.
Thanks

ML