Thanks!
I really want to run a 275/35R18 all the way around, but am struggling to find a wheel that works and doesn't cost an arm and a leg. And even with the right offset, sounds like a 275 takes a little work. Not opposed to messing with it, just easier if I don't have to.
If I am honest with myself, the rear has to have a 275 (or bigger) tire, the current 245 just looks too small proportionally back there (IMO), but the front would probably be fine with a 245/40R18 or the 255/40R18 you are running. And if they fit on a 18x9 +24mm wheel, that costs half what I am seeing for an 18x9 +35mm wheel, all the better.
Besides, part of the reason I want to run a square setup is so I can rotate the tires. But there is a good probability that the rear wheel will end up with a different offset which pretty much negates the idea anyway.