1989 Johnson J4RDHCEC impeller question

[electman3102]

Good Neighbors: If anyone can tell me how to replace the impeller on this
motor, I sure would appreciate it. Do I have to remove the propeller shaft or
can I just unbolt the 3 bolts, 2 on rear bottom and 1 on front top, of the gear
case fin and pull the driveshat out of the power head? I have unbolted the 3bolts and can't get the gear case to disconnect from the mid section. Please
give me some advice. I have an original Johnson service manual for this motor
but it does not fully explain the procedure. Need answers in the bayou country! Thanks a million!

[boats.net]

Remove three bolts and gearcase should drop down.