need help with mercury v-6 trim unit???

[jcb1968]

How do you get the pin out of the top of the shaft? I have taking the 3 bolts out of each side plate and the 2 nuts and washers off the back and even went ahead and took the 2 sideplate off completely,but the trim unit is being held on by that one pin and i can`t figure it out. I do know that one end of it has a slot in it,but it don`t turn or anything. and when I try to knock it out from either end with a hammer and punch,it is dead solid. So what holds this pin it?
Thanks,Jeff