Show me a Ford coolant line that burst in these 97-03 models and I'll shine your shoes for a week lol. Ford really did something right here, they will outlast the vehicle. Yes, they will go bad at those band clamp connections over time unfortunately. When replacing, you should use expanding clamps -
Was it wet in the plug chamber? Did you blow it out to verify? They leak @ the water pump tube and manifold connections intermittently. Unless the hoses where changed and clamped up top at the heater core ? That's a big mistake lol. Well, unless you used these -
Pop the hood after it rains, maybe you have a bad seal ? Make sure your harness isn't resting on top of your AC accumulator. Did it sound like a rod knock when #4 went?
_______________________________
You can cut the Ford hose ONCE and reconnect, but use those clamps. They require very little torque and are solid,- won't tear into the rubber.