I'm trying to replace the water pump on my 1996 25hp Johnson (long shaft).I have everything disconnected including the shift rod, however the nut that remains on the shift rod will not pass thru the existing water pump to allow me to completely remove the bottom section of the lower unit.what is the procedure to allow the shift rod to come out with the bottom part of the lower unit? Is there something else that must be disconnected at the power head?