Mercury Mariner V-250 V-275 Outboard Service Shop Manual 1990, Page 175Get this manual
7Thread 5 16 18 bolt into the pivot pin, (one each side) to aid in removing pivot pins Remove pivot pins, washers and springs gDrive out the pin that holds the trim cylinder pin into the upper end of the trim cylinder10With blunt object (so as not to damage slotted ends of the pin) drive the upper trim cylinder pin out of the swivel bracket (support the trim cylinder as it will fall free when the pin is removed)
aPivot Pin (One Each Side) b-SlSI1: 16 BoltWasher (One Each Side)