No spark tp coil?
 

1991 F250, 460 will turn over; but won't start. Replaced coil; but, still no spark coming from coil...what next? Recently replaced 2G alternator with 200 amp 3G, that's when starting problem started...?

Thanks,
Bob

you need to have 12v to pos side of coil and earth switching to neg side. check fuses and power supply first...