Leaking Coolant - Help!

[Ron Katona]

Remember the parts car I'm trying to sell for $750? I replaced the
radiator, all related hoses, and the thermostat today. Checked the old
radiator and I couldn't find a leak, but I figured under pressure it
might have been bad. It was full of gunk anyway so for $150 it was  time
for a new one.

I finished and double checked all connections. Everything looked good
and I started to pour in a 50-50 mix of water and antifreeze. The guy
next to me asked if I was spilling, or if it was just leaking out the
bottom.

Well damn.

The leaking fluid seems to be coming right from the bottom center of the
radiator as I look from underneath, but it could very well be traveling
from somewhere else since I know the radiator is good. Looking down the
radiator from the top I can't see anything leaking from any hoses or the
radiator itself. Considering what I replaced today and not seeing any
obvious leaks from the hoses and such, what's the most likely leak in
this area? The big heat exchanger in front of the radiator is for the
A/C right? Where's the heater core? Any help/advice greatly appreciated.
--
Ron Katona