I've searched all over this site and others and can't find the answer...

I just won a set of 6 Aurora gauges and since I was planning on switching out my stock gauges anyway (though I was going to go with AutoMeter gauges, I can't complain about free gauges) this is awesome. The problem is that the speedometer in the set is electronic and not gear driven. How do I convert to this setup?

The truck in question is my 1976 F250 4x4 with a C6 transmission.