Those 3.0 V6's  were great engines. I had several. I still have a 2001 ranger with one. The only thing about them is they don't tolerate overheating at all. The head gasket is the weakest part on those. I had a Taurus with a leaking head gasket. I drove it that way for years. (kept a gallon of antifreeze and a gallon of water in the trunk).

If yours overheated (coolant loss) and you didn't find a leaking hose, radiator, or heater core then where did the coolant go?

Anyway, maybe change the plugs. Before you do, crank it real shortly. (maybe 2 seconds)

See if you find a wet one. It will be easy to see which one(s) are wet with coolant, change it (them) and see if starts.

Then watch Scotty's video on testing for combustion gasses in your coolant system with a Combustion Leak Detector.

On the top right of this page there's a TOOLS link and then click on Testing Tools. Scotty recommends an inexpensive one.

If you spray a little starting fluid in the intake and crank, if the engine tries to start you have ignition and the problem would be fuel delivery. If it doesn't try to start you have no spark. (Possibly the crank sensor was cooked when it overheated.) Of course this assumes that the engine is OK internally.

How long did it overheat for?