Help with diagnosis please, have tried to find issue, am stuck, no OBD1 Code Scanner, truck was running fine, all of a sudden engine dies and will not start again.......alternator, battery, timing belt have all been replaced before this issue started, was running great....

Motor spins, acts like it wants to fire, but never does........have had someone turn over vehicle, sprayed starter fluid in throttle body, nothing, thought no fire, took plug wire off of coil pack, put screwdriver in coil pack, held wire close, spark was there, just not a big spark......I don't know if the coil pack is bad, is there any way to test it?

Any ideas would be greatly appreciated.........
Thanks,
Greg