OK, I looked at the Speaker Motors document, and I think I found the answer I was looking for; however, as Wayne indicates the crossover I'm working with is not exactly the same as the ones in the doc.

Using one of the Pi 3-7 crossovers, 300 W RMS put 100 W RMS across the tweeter resistor. But, practically speaking, 40-50 W power rating for the resistor has been found to be sufficient, because of the usual balance of energy in program content.

In the Pi 2 crossover, however, there is only a single capacitor leading to a tweeter resistor. No inductor.

If that does not mess up the calculations, then I could run four ten-watt resistors in series to make the required power dissipation. Right? I would never plan to run more than 300 W RMS into the speakers--probably quite a bit less.

Thanks again. Just trying not to set my speakers/house on fire....