There's a transverse pin visible in the drawing and your
photo. It comes out. Then there's an internal spring clip just inside the mouth of the conical section. It come out. Drive the shaft out from the
wheel end, using a copper hammer or piece of
wood to keep from damaging the threads for the
wheel nut. Then slide a brass puch or equivalent into the hole and catch the
interior edge of the farther way bearing, and tap it out with a hammer. Turn the unit the other way up and do the same for the other bearing.
Measure the bearings carefully, and order new ones:
https://www.mcmaster.com/standard-ba...oller-bearings
You may need a few new tools. Brass punches are very useful for this sort of task, because they don't destroy the
steel involved - the dents are in the softer punch.
https://www.amazon.com/Gray-Tools-C2...NsaWNrPXRydWU=
A copper hammer also helps. I just about built my whole
boat with one:
https://www.amazon.com/Thor-Copper-H...s%2C231&sr=8-3
From you picture, it doesn't appear that you are going to have quite the problems others have had with this task, because I don't see rust. Get that transverse pin out of there, and go for it.