9" +15mm is a big ask, probably better to stick with off-sets that work. I had mine rolled by 'precision guard rolling', don't know where your located, but contact him and he will put you onto the right person in your city.
He did the flange 3sgteTurbo is talking about no problems, and put about 5mm flare in the quarter.
$60 a corner plus $50 travelling time. Leave it to the pro's.
http://www.guardrolling.com.au/