Okay sending unit reads 10.6 on the full which makes my gauage go to the full mark. Sender reads 80 on against the empty stop gauge reads empty. Great Now is where it gets intresting with sending unit reading 47.5 it just moves gauge off empty mark with 5 gals in tank, add 5 gals at 34.8 ohms gauge now reads 1/4 tank, add 6 gals total of 16gals get reading of 19.4 ohms gauge reads between 1/2 and 3/4. I don't think I can get 3 more gallons in tank so I'm saying its close to full because gas is up into fill tube. So first is even if I could get 3 more gallons in it that shouldn't take gauge from between 1/2 and 3/4 to full or take ohm reading from 19.4 to 10.6. Honstly I think its phased wrong or its wrong unit for Plymouth 19 gallon tank. All I do know is the old sending unit which came from Mancini was right on the money. Which makes me think this unit is just phased wrong. What are your thoughts?