This was very quick and easy to to actually!
I transferred the 11i client (basic and the SQL*Plus bit) to my central server, and extracted out the software.
Then I copied the executables to my bin directory, and the libraries to the lib directory.
Finally, I moved glogin.sql to my sql directory.
All I then had to do was amend the profile to set an LD_LIBRARY_PATH variable.
The only thing left was to ensure SQLPATH was set, and then set TNS_ADMIN variable to where I am housing the tnsadmin.ora file.
Hey presto! an 11i client install which can connect everywhere I tell it that it can get to.