Editor

What I'd suggest is an interactive function bound to some key which does a 
gnudoit (? is this the Emacs name?) to stop whatever server exists via 
(server-start t), then does a (server-start) in the current instance. So 
then you can switch which emacs your emacsclient invocation talks to with 
a single keystroke.

Alternatively you could set `server-name' on the servers and use 
the --socket-name argument to emacsclient.

There are more elaborate methods but these two should work.

I'm afraid as an XEmacs user the multi-tty stuff just works for me ;)