TBh mate i think your best bet is removing them from the Car. Checking the offset ( plenty of info on google to see where to check this )
And then simply speak to ROTA them selves and ask what offset you should use for your car.
It will be far easier to sell these wheels on and buy the correct offset. Rota wheels sell very fast and i don't think you'll have a problem finding another set.
Just thinking it is better to change the cause of the problem than to change everything else around it to work around the problem itself. Cheaper and faster in the long run also.
are you wanting to go for the "HELLAFLUSH" look or to get these wheels to actually fit properly. ?
OOOOOOOOOOOSCH