Two independent SSHD processes?

[CLOSE Dave]

I'd like to run two SSH daemons on the same machine. They will listen on 
different ports and have other differences in their configuration. I 
want these two daemons to be independent of each other: either can run 
while the other is stopped. I need to do this for recent (systemd) 
machines and for older ones (SysV).

I'm finding that, although the SSH daemon records its PID in a file, 
that file is not configurable. Consequently, it seems that stopping one 
of the daemons causes the other to also stop. Same for starting one.

Here is the procedure I'm using to setup the second daemon on SysV. (The 
first one is the standard daemon normally running. I haven't tried yet 
on systemd.)

cd /usr/sbin; ln -s sshd xsshd
cd /etc/pam.d; ln -s sshd xsshd
cp /etc/rc.d/init.d/sshd /etc/rc.d/init.d/xsshd
# edit /etc/rc.d/init.d/xsshd to reference a different config file
# and the new program name, xsshd
chkconfig --add xsshd

I realize that I might be able to workaround these difficulties, or some 
of them, by revising the standard system control files. I'd like to 
avoid doing that and just fit within the Fedora framework. Is that 
likely to be possible?
-- 
Dave Close