To keep grease off the shaft during installation of the v-ring shaft seal I found this dental pick at the pharmacy. The curved shape allows me to get into tight spots with accuracy.
Lay down a nice bead of grease in the seal race. This is a standard axle grease.
I made this simple tool to install the seal. It's a piece of round stock with a 0.65 inch hole bored through it. A piece of wood with a hole drilled in it would also work.