[dsraven]

grab one of those cheap mirrors on an extendable stick from the auto parts place or dollar store, look at the under side of the water pump, there is a weep hole behind the pulley to drip out anything that gets past the seal. also could be running down the lower rad hose if the leak is bad enough. for a frost plug leak, put on some safety glasses and stick your head under there with a flashlight and have a look around. otherwise get a pressure test done or buy the tester and do the pressure test yourself. pump up the tester to the rating on the cap, usually about 15-16 psi. it should hold for a few minutes, engine off and cold. if it is leaking out the backside of the flywheel area then it could be a frost plug leaking behind there. really check the intake manifold gaskets at each end of the heads because chevy used plastic gaskets for a few years and they crack over time. it could be leaking coolant inside the engine too, if this is the case..