I think it's ok if it wiggles a tiny bit if memory serves. The more interesting question would be if you used the right rotor and wires.
You see, the 4.5 has a weak (by modern standards) spark system, that requires non-resistor wires, and a non-resistor rotor. There are resistor rotors and resistor wires available. The OEM set had resistor plug ends, but the wires were solid copper.

Take a look at the ohm measurement on your new wires and compare to the old. Make sure your rotor is also not a resistor rotor.

Lastly, make sure your firing order is right. This isn't an American V8, the firing order is 1-5-4-8-6-3-7-2, and 1 thru 4 is all on the passenger side, and 5 thru 8 is on the driver's side.