Is overspray on cylinder head ok?

If it were a 318, I probably would risk the minimal cleanup and gamble approcach. A little more hesitant about a 360, because I'm not tripping over them like I am with my collection of 318 cores. But given the availabilty of engines (not to mention the probable cost of the initial investment), I'd go the extra mile. To me, it's just not worth risking irrepairably damaging a real deal 340 block.