I am looking at buying an Innovate wide band air fuel ratio gauge, just wondering if anybody here as much experience with these. Looking at using it more as a carb tuning tool, than something I plan to install permanently, as I would like to use it to dial in both the 428 CJ in my 59 (unleaded premium pump gas), as well as the Fairmont, which usually burns VP C12 leaded race gas. I understand the leaded fuel will eventually foul the O2 sensor, so I would prefer to use it on the 59 first, just wondering where I should weld a bung into the exhaust system. The 59 has FPA shorty/mid length headers, I have heard of some guys just drilling a hole for the O2 sensor close to the tailpipe outlet, but I know when working at Toyota, the factory tended to put O2 sensors quite close to the cylinder head, some only a few inches from the exhaust ports in the exhaust manifold, others still usually less than 2 feet from the head(s). As for the Fairmont, which currently has a 347 SB Ford in it, the headers are long tube FlowTechs, which have a bung already welded into one primary tube on each bank, just ahead of the collectors. I run no mufflers or pipes on the Fairmont, just a short turn down, to mainly divert exhaust fumes from wafting into the car thru the shifter hole. The 59 has a full 2 1/2" exhaust system all the way to behind the rear tires. Anybody know how long it takes for the leaded gas to foul the O2 sensor, and once fouled, is it junk, or is it possible to clean it ? (Carb cleaner?)