A guy gave be this stuff after going over to the 4.6 Mustangs. IT has 3 replaceable chips for the revlimiter 6000,7000,8000. Ford Part#M-12199-C301
I dont know anything about them although I'll bet you need the matching distributor. Is there a selector switch for number of cylinders? If not, your stuck with what ever the thing was built for. Is it for a six? If so, it would throw the rev limiter off if you got it to work. Plus those are pretty big gaps between the limit settings.
To me it looks like a ford ignition control module with a factory rev limiter feature and matching coil perhaps. Fords version of an MSD or maybe even an MSD product rebadged for Ford? Since it is a Ford Motorsport part it can be cross referenced in a catalog I'm sure. I would bet it is for a 5.0 V-8.