If you drive along Great Eastern Highway from Perth and proceed to Guildford, you will find a turnoff to the north (left) near the Guildford Town Hall (which is on the south side of the road)
which leads to the Swan Valley.
On the left of that road, within 50 m of the turnoff, there is a park. On that Sunday, there should be a goodly collection of French cars.
That's where it's been in the past few years and that's where I expect it then.
How long are you in Perth? You may care to inspect my 4CV and R8.