Port 8443
And then try without leaving *THAT* ssh session. Open a NEW terminal
ssh -p8443 -lyouruser yourhost.yourvps.com
Ensure it is good. Fix if needed.
Here is a config example for your Desktop (System A.)
This config setups the redirects pointing at your hosted mail server (System C) through you VPS server (system B)
greg@omg:~ [0] $ cat ~/.ssh/config
Host redirects
Hostname yourhost.yourvps.com
Port 8443
#Outgoing mail delivery sstmp/esmtps
LocalForward 1465 hosted.mailserver.com:465
#Inbound mail pickup (IMAPS)
LocalForward 1993 hosted.mailserver.com:993
# Inbound imap, not needed is using imaps
LocalForward 1143 hosted.mailserver.com:143
Then just point your mail client at "localhost" or 127.0.0.1 with the proper port for the proper service and it is done.