If it is stuck in the swivel bracket portion of the assembly, there is a flat ground on the pin that allows grease to move from the zerk fitting down to the bottom of the bracket. The co-pilot plate has two ears that ride into two slots cut into the top of the swivel pin. The ears can be broken off if you place too much force on them. The best option is heat, and don’t worry about using too much of it. Once you start to heat it, the grease, what is left of it will start to run out and perhaps loosen the pin. I have an extra pin if you end up needing one. I am going to be running some motors, so I won’t be on here much for a week or so, but I will check back.
Steve