The AEVA has been helping Australians convert cars to electric drive for almost 50 years. Below is a collection of articles you might find helpful if you are considering a conversion project.
Introduction to EV conversions (A great place to start)
The Geelong sub-branch has curated a great list of suppliers for EV conversion parts.
Last but not least, visit the AEVA forums for a wealth of information generated by Australians who have been converting vehicles for years. Once you've digested your fill, sign up and ask your own questions!