Background - I'm a British National currently in Australia on a working holiday visa. In November I'm planning on travelling to Argentina picking up a rental car, crossing the border into Brazil and driving to Rio. After a some time in Rio I will drive back to Buenos Aires.
The UK government states I will require an IDP 1949 for Argentina.
For Brazil it states my UK photocard license can be used however an IDP 1968 is recommended.
Ultimately my issue is I cannot apply for the IDPs from within the UK. My solution is to apply for a Western Australian license, then get IDPs for that license.
My fear is that when crossing the border I'll have an Australian license, IDPs for said license but a British passport.
Could this lead to a problematic time at the border and possibly be denied entry?
Grateful for any assistance provided!
EDIT: I plan to drive back to Argentina.