I pulled these weights for a MX6 off of a post in the 1st gen forum. Sleepcounter posted them, they were referenced and accurate.
4WS 2888 lb (4ws turbo)
GT 2705 lb (2ws Turbo)
DX 2535 lb (I don't know the relevant models in Oz)
LX 2615 lb (I don't know the relevant models in Oz)
lb to kg is approx. lb/2.2= kg
Throughout history, 2 doors have been heavier than 4 doors (ie. Falcon hardtop & Holden monaro) but I don't know if that is the case with the MX6 or not.