Thank you for keeping the thread alive
I don't know about the past of this car. It looks like it has been neglected somewhat before the previous owner decided to have some stuff fixed, but I don't know if gasket #113 has been replaced. I agree I should change it, but with my luck I wanted to keep my intervention in the car to an absolute minimum, and taking it to a mechanic is not an option at this time.
Jeffry: I'm afraid I didn't mention something very important: the leak happens even at idle. I'm fixing other things on the car (interior stuff) and I don't drive it much... just a few miles every other week to keep the battery charged. The last time I looked under the car -after being parked a day or two- I saw a large pool of coolant on the floor, and when I started the engine to see where it could be coming from I saw the large amounts of coolant dripping quickly under the car, around the driver side rear cradle mount. The pool of coolant on the lower intake manifold has always been there and the area under the throttle body looks wet, so my assumption was that it came from there. I might be wrong, though...