Water pumps, T stats and radiators are all common items. Make sure you dont allow then engine to enter the red even for a second if possible, as the heads on those engines are basically made of glass. I would check Tstat first, but its very possible the impeller of the water pump has come apart in the block, which Ive seen many times. If you open the coolant res cap while the engine is just above cold, NOT hot, you should see a slight pisser stream of water right at the top of the res. This will let you know the water pump is doing its job, or the T stat has jammed shut. Hope this helps.
-Ben