Slight misfire question

[Koast]

I have a 98 vortec 7.4. I changed the plugs,wires,cap and rotor. It's much better but still a slight misfire. Is it the ignition coil or am I way off? Any help would be appreciated.

 

[skylark]

Check the distributor drive gear for wear. Also the 7.4 had some problems with injectors.