Ok. Firstly, do you need to go as wide as 275?? On a 9" rim, recommended size would be 245 or 255 with 265 being recommended maximum. I'm running 8.5J on front with 35 offset so your rim will be 3.6mm less sticking out than mine at the outer rim and 16.4mm closer to the hub on the inner.
You should be ok on the rear as I'm running 10.5" with 40 offset with 275/40 tyres (only 19" rims) and no rubbing even when I've fully aired out my air ride.
Personally I'd maybe think going slightly narrower tyre on front????