Considering what parts you have changed,
and since you do not list replacing the ignition wires,
I would suspect the long coil to distributor cap center wire.

First take that wire off and check if you have spark from the coil HV terminal to ground while cranking.

I now check ignition wires by wrapping aluminum foil around the outside and then using an old crank Biddle Mega-ohmeter using the 1000 volt output.

If you do not own or could borrow a Mega-ohmeter
I would remove the Magnum coil to cap wire from your Ram
and install it on one cylinder of another vehicle with a known good ignition system.
Start that vehicle and run a grounded wire probe up and down the insulation of suspect wire looking for sparks and listening for missfires on that cylinder.