I bought a Spectra Premium FG67A and the resistance sweep was about 10 - 80 ohms. It is off by around 1/8 tank on the gauge, there's more fuel than shown, I can live with that, maybe some day I'll play around with bending the float arm for better accuracy. This forum did teach me a mod to add a ground wire which I did. I have two YouTube videos (before and after) of an A-body sending unit I fixed for a friend with that modifications. The picture was taken from Moparts,