jeep closed cooling system ??

[powerstrokin04]

I have a 89 jeep comanche with a 94 h.o 4.0. The cooling is still the old 89 closed cooling with the pressure jug. It does have the newer style thermostat housing. Does anyone have any input on just converting to open system with the newer style radiator or just put a inline coolent filler with a rad cap and overflow bottle? thanks wes