Not to bad mouth MSD, but to keep it simple the MSD 6 Series boxes are CRAP. They are OLD technology, and are VERY unreliable. When it come's to power, they are behind as well. I own a small performance shop, and I've sold my fair share of MSD boxe's and 3/4's of them end up coming back on warranty or for something else. I learned my lesson as well when I went through 3 MSD 6AL's in one year. Crane make's the best ignition out there right now with there 6 Series digital igniton. I've been using the Crane box and PS-92 coil for year's and have never had a problem. I just recently purchased there new Elec. Distributor(Unbelievable Product) as well for my 408 and I love it. I get alot of customer's coming in for an MSD 6 box, but they usually end up walking out with a Crane once I'm through with them. Spend a bit more money were it count's and hook yourself up with a Crane HI-6. (Get the one with boost retard as you are planning on a blower) I don't believe Crane make's a distributor for F/I 5.0's so go with an MSD billet unit I guess. Check out Mallory, I've sold a couple of those and they seemed pretty decent as well. Overall MSD is a great company, but stay away from there CD Ignition boxes. If you don't you will regret it in the long run. And you know, alot of people will reply to this post with, "I've never had problem's with mine,"...... well just wait a bit longer and see, either that or you just got lucky.