[metalsmith]

Well I only need one for the monitoring. I'm carbed so I've got no computer to tune. Just a need to see how well it's tuned after I tweek the carb stuff. :-D

I think it was Summit (a search for "air fuel" on their site will give you plenty of options) that has a reasonably priced (200-250) O2 sensor that mounts on the dash. Other wise you will need a sensor, an interface to interpret the signal, cables to connect the interface to the computer and software to interpret the signal from the interface.