according to the tire conversion i used (online of course

) that works out to about a 32.8" tire diameter..
Thats a tricky size to decide.. you can get away with 32's on that much lift, but most of the time a body lift is needed to comfortably fit 33's.. and a 285 tire is wide, prolly 11.5 inches wide... I think it depends how much wheeling you're gonna do.. if you're going ot be flexing the suspension, you're prolly going to be get a lot of rubbing.. but if this is a street D with big tires for looks, you might be happy with it...
I've got a bit of sag in my Tbars right now, and my new 31s are rubbing on the bottom corner of the bumper..
if the deal is good enough, and you have some padded pockets, you can always buy them, and re-sell them if they don't work out for you..