Quit runnin

Ok, got the box checked out... it's bad. The guy at the local speed shop took it and gave me a new one even tho I didn't get it from him (THAT ROCKS!). so I fired it up and my tach is still stuck on 3000 rpm. And I noticed that my alternator is only putting out 11.5 volts. I am wondering if a spike from my alternator messed everything up?
It is a Powermaster 1 wire 100 amp deal, belts tight everthing seems OK.
Then I looked at my Speedo, which is new and reflects actual miles on the car since I put the engine in it. I'm not superstitious or anything, but the miles are at 666 :twisted: , which figures because its giving me a hell of a time!!!!