I just want to add some clarification to your excellent answer. Yes, there are two design types, pin and spade. The spade design is superior to the pin type. Unfortunately, the pin type harness is no longer available from Jeep/Chrysler.
Spade type harnesses are available for about $20 (Chrysler P/N 5102401-AA). Of course, the coil will have to be replaced if converting the harness. When ordering the harness and coil, order for 1997 Jeep 4.0/5.2 (they use the same coil). 1997 was the model year in which the conversion from pin to spade was made.
I have done this conversion on at least half a dozen customer vehicles, and all are still running as they should.