I can only tell you what I've experienced with this car. I have a 04 sxt since it was new.Back of engine. Hard to tell as I can’t fully see. But it’s as peva said, it’s dripping towards the back, from the bottom.
Keeping a thing of coolant in the car for now, as it’s fricken cold out and I don’t have heated garage. And I’m in mid minnesota.
I’m looking at fel pro gaskets, around 30 bucks. Comes with two o rings? So I’m guessing that’s the heater o rings?
I had coolant leak isues. Sounded very similar. I had just changed the radiator( from oreilly's) , the thermostat, and the hoses. I thought it might have been what you are looking at. It wasn't. Do yourself a favor. When you notice it is leaking, feel the bottom of the fill tank. if it is wet, it is either your tank or the cap. Mine was the cap, as I had just replaced the old tank. You said the there was no pressure and that piqued my interest. These cars have highly pressurized coolant systems. The caps wear out (or are defective) and the tanks wear out and are easily clogged or they leak. I would check this first.