Aftermarket Ignition

[Mrturner1]

I've been looking over the Jegs catalog and thinkin about getting the whole ignition system upgraded to MSD. I know what the distributed does, but I was looking at my engine yesterday, and I don't see a coil (like the msd blaster for example). So is this an add on type thing or am I missing mine? And what's the benefit if it is just aftermarket? Also lookin at an MSD 6A box, if there's something better for a street/strip weekend ride let me know. And also what's the benefit of that as well?

I know more fuel/air/spark = more hp and tq, so do the 6A box, the coil, and the distributor all have a place in making more spark, or are they just sellin parts?