ASA 5505 - site to site VPN and PAT IP

Hello all, I am a little stumped and could use a hand!

Here is our network design
img190.imageshack.us/img190/1006/vpnconcept.jpg

I had a pretty good sample configuration of exactly what we want (LAN-to-LAN Tunnel Between ASA 5505 and ASA/PIX) here

www.cisco.com/en/US/products/ps6120/prod...186a0080950890.shtml

But the Main office IT group wants us to PAT our private IPs to a single IP (10.70.4.70) for the tunnel. How would I incorporate that with the above configuration? I tried several ways

nat (inside) 1 192.168.1.1 255.255.255.0
global (outside) 1 10.70.4.70

but then I couldn't figure out how to route to the internet from there. Also, I don't know if it's better to PAT to that IP all the time, or only for the tunnel.. is there a cost/benefit in performance?

Appreciate any help you can give!

hmm well i give up

[code:1]access-list vpn-nat permit ip 192.168.1.0 255.255.255.0 10.1.130.0 255.255.255.0
!
static (inside,outside) 10.70.4.70 access-list vpn-nat
!
access-list vpn-data permit ip host 10.70.4.70 10.1.130.0 255.255.255.0[/code:1]

Hope this helps

This way you can make your L2L tunnel and still have a connection to the internet since the destination addresses of the internet are out side of the private IP ranges.
I have to warn you tho. Using this setup might cause problems with the stability of the VPN.