Displayed (I hope) are two photos I picked off of fordbarn some time ago, that someone posted. it looks to me to be an excellent way to remove the seal. I have not made the tool yet, but will do so next time I have to remove some seals.
The tool is made from a discarded rear axle.
The new seals on the market that most suppliers carry are too big and you will have difficulty installing them unless you reduce the outside diameter in some fashion. The seal is apparently for some other application. The only supplier I know that carries a seal that fits correctly is A&L.
Tom Endy