I'm quite new to networking and am trying to set up my first VPN connection.

The Situation:

I have been contracted for some programming at a facility some distance from my location. I would like to be able to set up a simple VPN connection to their network so that I may make adjustments without significant travel.

Their Current Network:

Six devices (one I need to connect to) plugged into a basic router (Dlink). This router has an internet connection and a static ip address.

My Hopeful (questionable) Proposal:

I attach a VPN Firewall I happen to own (Netgear FVS318) as device number seven on the client network. I disable routing / DHCP in the Netgear. I forward the appropriate IPSec ports from the Dlink to the Netgear. I then create a VPN connection on my office Windows 7 machine to the remote network. The request is forwarded from the Dlink to the Netgear where the VPN connection is authenticated. I now have a remote-access connection from my office PC to the client's local network.

The Question:

Will this proposal work? If not, would another possibility be to attach a computer with a VPN server to the client network?

Also, as a note: the client has requested I not replace their router or place mine in-between theirs and the internet :(

Thanks very much!