Just find an acceptable location in your exhaust ( near where an efi car would have an o2) cut and weld a bung. Plug in the 12 v power cord to your cig lighter. Download and read LM-1 manual. Start logging a/f. Google their website and they have a tech help forum. We have the LM-1 with RPM converter. It allows us to read a/f, and 4 other items. In my car I read a/f, intake temp, rpm, and tps. In the carb car we read a/f and rpm. Check that website out. There are other companies but like I said this seems to be pretty simple.