water in lower unit, can't get it apart...Please?

[new2obrepair]

1984 Yamaha 15sn 2 stroke. have done a lot of work recently as can be seen in earlier posts. The help I rec'd here gave me the confidence to carry through and solve the overheating issue. But in so doing it,I must have damaged the seals in the lower unit. I found about 2/3 water to oil in the lower unit after this mornings run. <br /><br />Now I can't get the base of the water pump off which is stopping me from dissasembling the unit. My manual says to use 2 screwdrivers. I do not think that is right, I've tried that with considerable force and failed to budge it. I cannot find any screws or bolts to hold it in place. Do I have to remove the prop and output shaft, then pull the pinion gear off in order to pull the input shaft as a unit? I need this help guys, please come through? Thanks