Re: 1973 Evinrude 65hp Water pump
the shiftrod will have a pin or screw holding it in place, the method of fastening changed ever so often so I'm not sure of yours exactly, but it will be under the bottom carb and require some dexterity and probably a socket extention to reach. Some grease in the socket improves your chances of not dropping it. check the manual
when you mate the two halves, you might have to rotate the flywheel just a tiny bit to mesh the splines - no fasteners there. manual calls for molly lube on the splines, the OEM water pump kit includes a little packet of it, but not on the top of the driveshaft, the clearance is too tight.
manual also calls for "OMC adhesive M" on both halves, I have in the past substituted permatex #2 with no problems, but that joint doesn't have to hold water or anything.
I pressure-tested my L/U with a 12V air compressor (small roadside-emergency tire inflator kind of thing with a built-in gauge), and the hose that comes with one of those $10 plastic gearcase oil changing pumps that screws into the drain hole. I found a piece of 1/4" pvc hose that made a good adaptor along with a couple zip ties. pump it up to 12 - 15 PSI and see if it holds. But myself, I usually don't do that unless there's water in the gear oil.