Since you've had no response I will reply, I specialise in this area and could offer a no charge initial consult if you would like.
I am based in Adelaide but have many interstate clients so distance not an issue for us.
Feel free to email me if you wish to get in touch: Andrew@vistafs.com.au
FYI we sponsor the parent site to this one and have done so for over a decade: UK Pensions & Australian Superannuation advice (pomsinoz.com)
Yes you would need a white card to work on sites.
For WA it can be done online and is quite a simple process, I don't think you can do it before you get here as you need a WA address (as the other states have different requirements), they now also require you to put on PPE gear for a photo, the vest/top has to have reflective stripes.
I did mine through Bluedog training (https://bluedogtraining.com.au/courses/western-australia-white-card) about 6 years ago, it took less than a couple of hours then a phone call 24 hours later to answer a couple of questions (this may now have changed). The link will give you more info