Can anyone tell me where to pick up the VSS signal in an 09 Cayenne? I need it to install some aftermarket nav equipment.

If it's not easily and readily available as a direct pulse signal somewhere, is there a MOST bus adapter that will allow me to get this signal? It seems there are some options online (like the NAV TV MOST-HUR) but they're sketchy on compatibility and expensive.

Thanks.
- Dave