I didn't have time to make my own adaptor like I did for the W111 and Traction. So for the SLC I bought a 'novelty' plate but specified no letters. A ready made adaptor!
More here:
http://www.classicjalopy.com/2017/09/mounting-nsw-historic-plates/

More here:
http://www.classicjalopy.com/2017/09/mounting-nsw-historic-plates/