gif questions

[Chris]

In 14.10, it appears the description of setting up the VPN tunnel is  
built on a box
directly connected to the internet. The tunnel I'm trying to design  
is one level back
since the ISP router provides private address space host-mapped on  
the router.
Additionally, the example shows the creation of a tunnel for a single  
network and
I'm trying to accommodate multiples. So the questions are:

1. If one has private address host-mapped to the public IP by the ISP  
router,
should the tunnel reference the actual interface address as in:

ifconfig gif0 192.168.1.2 W.X.Y.Z
ifconfig gif0 inet 192.168.2.1 192.168.3.1 netmask 0xffffffff

where:
192.168.1.2 is the private address host-mapped to public via the  
local router
W.X.Y.Z is the host mapped public address on the other end
192.168.2.1 is the backend interface of this end's server
192.168.3.1 is the remote server's backend NIC.

...or should the 192.168.1.2 be given as the resultant public IP?

2. When creating tunnels to multiple locations, is the  
net.link.gif.parallel_tunnels
sysctl required? I was unclear if that is what's needed to have gif0,  
gif1 etc. or
if parallel as referenced in man gif means something other than peer  
level
tunnels.