1973 Mercury 7.5 Outboard Impeller - Does any know how to change the impeller?

Is it a big job to change out the water pump impeller?1973 Mercury 7.5 Outboard Impeller - Does any know how to change the impeller?You need to drop the entire gearcase, then remove the cover over the impeller. Look up top first and see if the shift rod disconnects near the powerhead or in the lower unit. Either way, plan an hour or so.1973 Mercury 7.5 Outboard Impeller - Does any know how to change the impeller?The best place I can tell you to go is to http://forums.iboats.com/archive/index.p there may be someone in here that can give you the answers. I go to I-boats for everything. So they may be able to help.