Hey Freckles, no fascia kit is required for VT/VX double DIN head units, but I'd recommend getting a wiring harness adapter to ease installation and allow you to refit the stock unit if you decide to sell the car later on.
If you're in Melbourne I can help with installation, I'm an ex-full time installer for one of the well known shops in Melbourne.
PM me if you need a hand mate.
Cheers.
CAR: VT Commodore Sedan audio car - SOURCE: 7" double DIN DVD/GPS - AMP: Pioneer monoblock / Pioneer 4 ch. - SUB: Kenwood DB+ 12" in 22lt slot ported box - REARS: Kicker RS60.2 splits - FRONTS: Kenwood KFC-S702P splits - MISC: Custom fiberglass iPhone4 dock moulded in center console, White / red LED cluster and dash lighting, SAAS Vortex drivers seat