So we can move on, I found a section in ADR 42/04 (General Safety Requirements) 2005 that covers this to a point, but nothing before the previous ADR (1989) which is probably why Perenties and other vehicles get away with it. Anything made after this new ADR came into effect shall comply with it, so modern vehicles have to meet the following -
Section 11 deals with internal and external protrusions -
Vehicle Standard (Australian Design Rule 42/04 - General Safety Requirements) 2005
Based on this I would assume that an Australian variant couldn’t have a side ladder from the factory and fitting one aftermarket would potentially be illegal, but no more so than a fishing rod holder, side awning and such so like a lot of things we do with our vehicles, it’s up to each individual to determine what risk they are happy to run with and accept the consequences of those actions. I this case, if you were pulled up I don’t think it would be too hard to remove it to keep the Police happy. Much lower risk than say running 35” tyres and a 2” lift on a vehicle it is not designed for.
Just my 2 cents. 😊