OK, i forgot i had access to RP Data
just looked up the land ownership
i was right, my plot above marked out on nearmap is pretty much spot on for adventure worlds main plot of land they own
i was also right the land south including the overflow carpark is separate lots... however !! adventure world own two of the lots south including the overflow carpark - they bought them both recently.
1 lot which is north lake road side - is 2.24ha bought by adventure world in 2010
second lot (overflow carpark) is 1.21ha and bought by adventure world in 2011
there is an annoying block of land though between the two of these owned by the state government (so the above two lots dont run seamlessly from north lake rd down to progress drive )
the main carpark itself shows as being owned by the state government
there is 3 lots of land behind the carpark and it looks like none are owned by adventure world. the one directly behind the carpark shows no ownership details - it is 2.61ha - then the land from there back to north lake road is 2 lots and they are both owned by perth waldorf school association.
phoenix road actually looks like it is slated to extend from north lake road down to progress drive along adventure worlds northern boundary.
so it would make no sense really for adventure world to own the phantom 2.61ha lot behind the 'state governments carpark' (which, for size comparison is 2.64ha)