Engine died....

[Sworn]

I have been trying to sort out my project Ranger and could use some advice....Yesterday I was letting it warm up in the drivewaywhen it suddenly died.........It fired back up O.K. though. I was checking the the trans fluid when I noticed it wanted to happen again. This time it didn't die, but the RPM's dropped almost as if something were constricting the engine. So far I've changed: plugs, wires, cap, rotor, fuel filter, flushed radiator for heater core, and installed a new alternator. I also just bought a new ignition module, as I understand they tend to go bad. (Ignition Module was more of a peace of mind thing.) Ignition Module is not installed yet. Thoughts? Thanks in advance!