@66fs runs 360 heads with 1.88 valves in his 273, he didn't notch the block, so yes you should be able to, he'd be the one to ask for exact details. I know he's a big 273 fan with 360 heads and 340 cam.
Stock 360 heads should be able to get 350 hp no problem, to get closer to 400 hp probably need to do some mild porting.