While doing a tune up on my Cadillac, I changed.

While doing a tune up on my cadillac, I changed out 4 plugs on the3 drivers side, then changed the rotor, and cap. I attempted to start it and it would only crank. I had the module checked, it was goos, the coil in the distributor was bad so I replaced it, and still nothing. I did not do anything but pull the old distributor, changed the wires one at a time, put a new rotor and cap on it and replaced it on the engine. When it wouldnt fire I pulled the coil fron inside the distriutor cap aznd replaced it, the module was goos so I secured it back in the distributor. I still can not get it to fire. Any suggustions?