My first suggestion with most "losing coolant" situations is to get a pressure tester (you can usually borrow them from Autozone and similar places). If the leak is external, you will usually find it.
On my '98, it was using coolant slowly when I first got it. I put the pressure tester on it and let it sit for several minutes, then I could hear the tell-tale drip off the engine. The leak was slow enough that the coolant would evaporate away instead of dripping on a hot engine. With the pressure tester on a cold engine, I was able to track the leak to a spot on the intake gasket (intake gaskets are a common complaint on these engines).
Another item to check (which you would likely find with a pressure test) is the heater hose quick-connect fitting that screws into the intake manifold, just behind the alternator. When these leak, they usually will trickle along the top of the pass side valve cover and drip off the back of the motor, making people think they have a leak somewhere else. It's an easy $12 fix, but don't overtighten. You can crack the aluminum intake pretty easily.
I also vote intake manifold gasket- 7-10 hours and $70 gaskets maybe $30 worth of fluid. Pain in the tail, but could be worse.
I also had a leaky radiator. The leak was maybe 4 inches from the top- it would leak down to that level and barely drop below it- despite the fact that steam certainly should have blown thru the leak over time.It dropped VERY SLOWLY after it dropped to the leak level.Ebay radiator was $160 new- seems ok after 3 years.
I would certainly look carefully at the much cheaper quicker fixes.
My recovery tank also did/does leak. It generally drops very slowly after draining the tank-.
I used the latest greatest set of gaskets- #98000 forget which aftermarket set, but it was #98000- they claim to be resistant to the red coolant(which many folks claim is the problem??)
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