I have been having problems with my engine missing when I get into the high rpms during hard acceleration so I decided to upgrade my ignition with a MSD 6A (#MSD-6200), MSD Blaster TFI coil (MSD-8227), MSD late model wiring harness (MSD-8874), and a set of Ford Motorsports 9mm ignition wires, all ordered from Summit Racing.  Installing the ignition was very easy and with the wiring harness I bought, it took me only 5 minutes to do the all the wiring.  I feel that this has made a significant improvement during hard acceleration and has smoothed out my idle a bit.

This is what you get when you order the Ford Motorsports 9mm ignition wires.  I am very impressed with the quality of the wires.  You may need to get new wire separators to accommodate the larger diameter wires.

This is the MSD Blaster TFI ignition coil.  If you are looking for a replacement coil, I would recommend this one.  It is exactly the same as the stock coil externally but with upgraded internals.

This is the location of the stock ignition coil.  All you have to do is unplug the connector, unscrew the four bolts and pull out the old coil.  Reverse the process to install the new coil.

A close-up view of the coil.  One end of the wiring harness I bought (not shown) plugs into the existing plug and the other end plugs into the coil.  It is very easy to go back to the stock configuration if I need to.

This shows you where I located my new MSD ignition box.  I removed the jack and drilled holes to mount the box.  I recommend if you choose this location to put the box as low as possible to avoid having the hood spring hit the box. 

I feel this is a good location and it was pretty easy to route the wires.  The wiring harness gave me just the right amount to allow me to run the wires along the firewall.  The whole job took me about three hours (box, plug wires, and spark plugs).