I have recently found several websites that have provided some information on Lithuanians in SA.
The welcome wall at the National Maritime Museum
This has 53 Lithuanian names on it, some from South Australia.
Western Australia Museum welcome wall
The State of Western Australia pays tribute to the large number of migrants from many lands and cultures who have played such an important role in the State's social, economic and cultural development.
Details of Steve Patupis can be found here, living at Eucla.
Architects of SA
Architects of South Australia is a database of material about the professional lives and contributions of a selection of the state's architects from 1836 to the present day. In addition to providing scholarly biographical information, the database also identifies the architects' principal South Australian built works.
Information on the work of Architect Antanas Lapsys can be found here.