Power steering gearbox leak

Wow, you guys may have just saved me from having to remove the steering box from my 66 barracuda. I was going to remove it (pain in the ***), and send it off to be rebuilt as it was leaking. From the picture, it looks like you are able to r&r the seal without removing the box from the car. Is that correct? I already removed the steering column, so if I can replace the seal without having to remove the box that would be a blessing. In addition to that seal, are there other seals on the box that are prone to leak? Thanks