i put a few tyres and some cushions off an old sofa mate... didnt leave a scratch on it at all
im sure just with the tyres it would have been fine the tip is to slide it over slowly and make sure the tyres are not on the soft parts of the body work ... put some nice sheets over them and it should be fine ... do it on the side with the petrol cap though as that side has more strength in the body pannels...
and spent about 3k on it mate... worth every penny....