I want to use an A/F guage but my car has no o2 sensor. I was told I could weld one into the exhaust and connect it to the guage but that is unreliable and doesn't read very accurate.. They said I'd need to get a wideband guage that would cost me ~$400... Anyone have any information on this? Buying just a regular $100 autometer a/f guage and using it on your mustang and getting a decent ballpark idea of if you're running rich/lean??? Or will I NEED to get a wideband one for even a semi accurate reading?