Sector shaft seal

[chero69gt]

    Hi everyone,
   
                      My 57 Custom has the original steering box, it works great,
  but yesterday it started leaking gear oil out of the sector shaft seal on
  the bottom. My question is, has anyone changed this seal? Also, do you
  think it can be done with the gear box on the car?
                       Any suggestions are welcome.

                                                          Thanks,
                                                                         Roger