We have had more Black/Roof/Ship Rat (R. rattus) records this year than Bush Rat (R. fuscipes), so it is probably R rattus, but I know of no way to separate the two species based on these photos. Important criteria, whether the ear can reach the eye, and whether tail length is greater than body length, are both impossible. We cant even try staring at the pads on the underside of the hind foot.
I assume the location came out correctly Jamie? (On the Corin Rd side of the ridge that bounds Tidbinbilla valley, a little way off Off Devils Gap FT).