The van and I survived the radiator replacement. Thanks for the advice.
A couple of observations:
(1) It took me about six hours to do this, but that included a lunch break, a couple of breaks to get out of the heat, and a trip to the store to get some distilled water. It also inclluded a half hour lost in fishing a dropped socket out of the engine.
(2) The van has 71,000 miles on it, and I was pleased to see that the coolant I removed still looked clean. In addition, the upper and lower hoses still seemed pretty solid. ( Unfortunately, they were pretty well seized to their mounting points and I had to cut them off. I hated that because I think they would have been excellent emergency spares.) Had the radiator not leaked, I feel like I could have made it to 100,000 miles before I would have attempted to change the coolant and hoses.
(3) I looked at the thermostat and elected not to replace it because it looked pretty clean and it would not come out of the housing easily. Access to the thermostat was simple enough that I think it would be a fairly quick job if the existing one fails.
(4) The youTube videos on the subject were helpful, and I wouldn't have thought about removing the cross bar to get access to the radiator if I had not watched the video. Nonetheless, the radiator was pretty tightly bound to the A/C condenser, and there wasn't a lot of play in the hoses to facilitate removal/installation. So I had to work with it for about 30 minutes to get it out. and about 10 minutes to get the new one in.
(5) Is there an easier way to drain the overflow tank than removing it? I tried a siphon pump, but it was minimally successful. So I ended up unbolting the tank and pulling it to clean it.
(6) Even though Dex-Cool is "factory approved", I went with Peak Extended Life (Yellow-Green) antifreeze. I had a bad experience with Dex-Cool on our Pontiac Grand-Am, and it destroyed all the gaskets.
So far, so good. I will keep a watchful eye on everything and probably flush and refill the coolant at around 100,000 miles.