Decided to save time instead of money and got water pump rebuilt by Bruce Madden, Atlanta GA. Bruce's message indicates this is the "last rebuild" on this core. Also suggested 2-stage thermostat. Nobody seems to carry those anymore. And I notice that one vane of impeller has very little clearance with the  housing. Will need to watch this as there is still just a bit of play in the new bearings. Actually, replacing the pump bearing and seals looks  easy if you have an arbor press and gear puller.

Anyway, I installed the rebuilt pump and gasket with Permatex pliable "form a gasket" (black sticky stuff that stays compliant) recommended by  dude at the auto parts store. After getting all hoses, timing belt covers, radiator etc. back on, I fired it up. Looks good. Sounds good.

Took it out for a short spin. Hmmm, do I smell hot radiator fluid? Pulled over and looked underneath to see the dismal peeing green fluid. Limped home with temperature rising...

Everything off. Undo the water pump bolts to find that the black goo has disolved in the heat and the gasket is destroyed. Cleaned surfaces with laquer thinner and this time tried silicone RTV "super blue" goo. Let it set for ~2 hours. Then assembled. Tightened again after a few hours and again the next morning. (Your not supposed to have to do that, but I'm paranoid now). Looks good again.
Everything back on again -- in only about half the time. I'm getting good at this!

Sunday - blue goo is looking  good. Took it out for a spin. Is the temp. needle reading a tad warmer than before or is it just my imagination? Will need to keep a lookout and perhaps change to a different thermostat - or stick the old one back in.

Future tips:
Put aluminum foil over timing belt to protect it. Leave thermostat and right aluminum intake casting attached to pump so you don't have to wrestle with the short hose while installing. Take the whole thing off at once, then disassemble. On reassembly, install timing belt covers, then fan, then radiator, then shroud. Bruce's single socket-head machine screw is a handy replacement for the one that is next to the distributor pulley.