Wilton for the New Sydney Airport
The MANS study [Major Airport Needs Sydney] of mid 1980's is the document/ reference to look for in this. Wilton site was around 10km east of freeway (from the freeway/ Picton Road intersection) on the Picton road towards Wollongong - and around 25km)
The Wilton site (centre is approx.-34.259912, 150.694656) , which provides a freeway access to Western Sydney (Sydney Airport is 71 km by freeway and Liverpool 51km and 31 mins - imagine a fast train down the centre of the freeway joining to the inter-urban system!!)
It was part of an old 2nd world war site on the top of the range.
Certainly bears a second look Mr. Fumble-ese!!