For reference, my car is an '01 Pontiac Grand Prix GTP. I assume many others use the same coolant outlet and bleeder.
The coolant outlet to the upper radiator hose (thermostat housing) has a bleeder screw for getting air out of the coolant system. The head of the inner screw is broken on mine, so I can't bleed it (which I'll need to do as I'm about to replace leaking heater hose coolant elbows.)
I found an alternative. Dorman part 13960, which is actually a brake bleeder screw.
Dorman Products
The original part had a bleeder hole on the side. The Dorman brake bleeder bleeds through a hose fitting. Actually might work better than the original, if you attach the fitting with a hose to a small reservoir of coolant. Squeeze the hose to let air out, release to suck coolant back from the small reservoir, even with engine off and thermostat closed. Probably want to put a vacuum cap on the hose fitting to keep out dust and grime.
