Welcome! You and your g/f should definitely come try autocrossing with us. With your modifications, you'd be in CSP (or NCSP if you'd want to run in Novice Class, which I'd recommend, or TCSP if you ran in Tire Class), and your girlfriend would be in LCSP (Ladies CSP). She'd be pretty much guarenteed a trophy in LCSP, since as far as I know, there aren't any ladies in CSP. :)
Come on up and join the fun!