La intake with magnum heads

I've come across a good deal on a m1 intake for a la motor. I'm looking at getting a set of magnum heads, and I know the intake and heads won't bolt up with out some work. I have seen some adaptors and have heard of redrill and tap the heads. Question is which way is better? Where can I find a template for marking the holes for redrill or where can I find the adaptors? Thanks!