I did it! I'm queen of the universe! Woo-hoo!

Watched the Hope video about 3 times - with this cute British guy, he finishes by hefting the hub with a pleased grin and going "Now, that's a good 'ub" - couldn't pull the freehub off with a neat snap since I had an entire wheel attached but squiggled around with a screwdriver in the gap and suddenly it just was loose. The pawls and springs were a brown, corroded mess, but I pulled the springs out carefully and flushed with solvent. The pawls weren't going anywhere. Then some oil, wiggled around, cleaned a bit, finally some grease, reinstalled the springs and wiggled until they seemed to work as cleanly as they were going to. Watched the video another 3 times and was dismayed to see that I needed a special "seal tool" to get the freehub snapped back in place. Could find ONE store that had it - but out of stock right now. Searched some more, found s forum with at least two people who had just worked it on with their fingers. And it was a doddle - the "seal" is just a plastic ring that I carefully pushed on piecewise with a screwdriver. So much for the special Hope HTT175 Seal Tool

And my wheel now has a new cassette and spins sweetly! Hah!