Pros and cons with A/F meters. I like having one as it is a good guide on where your engine tune is at but I'd also add a vacuum gauge. Both combined gives you a good picture of how the show is running. There are jetting recommendations for Webers to suit a 2.6 but to make the most of it requires modifications to the distributor so the advance curve isn't so aggressive (there isn't a specific ignition tuning guide for the ignition so it's trial and error mostly on a stock distributor)