Thanks for the suggestions. If I don't find a resource for doing the a/f testing, I will probably just increase the jet size a notch or two and go on. After the next road trip I can check plugs for the black sooty look. At some point though I will install a bung in one head pipe for an O2 sensor. A volt meter would then provide a real time approximation of a/f ratio while driving and under load towing.
Mark
