Another rainy day, so I tinkered around with stuff around the house, then we headed to the airfield and installed the resistor. Didn't work. As in the tach didn't read at all. Took it out, and everything's fine, so I think I'll ignore it for the moment, and maybe see about replacing the regulator at some point (you can take the tach feed off the regulator, assuming you don't have a Key West regulator. Which one do you think I have?). We put it all back together, and the tach works fine without the resistor. Bah.
In the evening, we watched I am number 4, which wasn't too awful bad - it looks like there'll be a sequel. Oooh, I hope it's in 3D </snark>