Hi Javier, I just lifted the car with a trolley jack using a plank of wood across the vehicle till I got it to the point where it balanced. I seem to remember it was 1,500mm in front of the rear wheel spindle but I can't remember if the fuel tanks were full or not - best to check your own vehicle - it only takes a minute. If you trailer is to be enclosed make sure it has plenty of ventilation or you will suffer corrosion after wet runs if things can't dry out quickly.
Good luck,
Phil
