i have taken a total of approx 120-130kg out of my car so far, and it still retains glass which is soon to be replaced with lexan, i installed a full cage which is approx 50kg, which leaves me with a car that weighs around 820kg, keeping in mind the things i didn't weigh stuff like the wiring and various engine bay bits and pieces which all add up. And after i install frp doors, hatch, guards etc i shoud see around 770kg i'll let you know when i'm done