Magnum Heads

What Are The Advantages Of Using Late Model Magnum Engine Heads On An La Block. And What Do I Have To Do Exactly To Use Them. Ive Heard That You Have To Change Intakes, Or Drill New Holes In Them To Bolt Them On. I May Want To Up My Compresssion And Heard That This May Help Without Any Major Machine Work. Kind Of New To This, All I Have To Go Off Of Is Advice From Experienced People Like The Guys On This Site. (very Helpful People) Any Help Would Be Appreciated.