How to clean a lower unit?

[RyanEC]

Hi guys, how or what would be the best way to clean up this lower unit from a late 90's Mercury 40hp 2 cylinder? Not to concerned about the outside as I will remove all the corrosion and re-paint, but how to clean inside from the water intake to the waterpump? Is there a way to reach inside? Guessing would have to remove the entire waterpump. Thanks!

 

[faztbullet]

Remove water pump and take a brass .410 shotgun cleaning brush and scrub passage well. Degrease with acetone and paint back passage with [FONT=Verdana,Arial,Tahoma,Calibri,Geneva,sans-serif]black appliance epoxy paint.[/FONT]