As an update, the huff n puff is working very well, allows me to stay on frequency for ssb conversations without constant dial twiddling. Yesterday I found that by adding two push buttons which feed ground or 10 volts thru a 100 megohm resistor to the summing node, I can tune the vfo up or down about 2 kc from the center frequency. This slow adjustment provided the careful tuning needed to get on frequency with the net, rather than jumping above or below the frequency with the vfo knob.
I will be adding one of these circuits to my HQ-170 to calm its ass down, cause it also drifts greatly even with a muffin fan, that runs quietly. I slow fans down by adding a couple of microfarads in series with the power line to provide a reactive voltage drop slowing the fan but still allowing good motor starting characteristics. Enjoy, woody