Bill, sorry to hear of the difficulty.
If you smoked the sender, it means you applied voltage to it. It is not supposed to have voltage to it.....or you forgot you have positive ground and applied voltage to it. In either case, you need to study as Martin suggested. Don't get wrapped up in measuring ohms and playing with meters. You are not getting any info that will help you. The gas gauge readings are not real accurate on 99% of old trucks. Old technology and dirty meter movements, goofed up needle attachment, slosh, Loss of ground, Chinese float arm got bent a little during shipment. There is a lot of possible mechanical variation between float and rheostat wiper. Between wiper and rheostat coil range.
At the meter movement: Between magnets, pivots and needle; and between needle sweep arc and hash marks on gauge face. Lots of large tolerances.
Take out the gauge, get new sender, wire it up properly on the bench and move the arm up and down. Report what you see before going any further. Member DADS50 has (had) a VID on here on how to bench-wire the components and test them. Maybe DADS50 can repost the information because it got lost during various "upgrades/versions/non supported software" somewhere along the line.
https://www.stovebolt.com/ubbthread...er/750427/Searchpage/1/Main/109807/WordsContinuing to maintain positive ground makes no sense. It will lead to mistakes by you and anyone trying to help you. EVERYTHING, EVERY part you buy is marked for Neg ground. ALL instructions are for Neg ground.
NOTE 1: Most gauge bodies/gauge frames need to be grounded. This ground, if necessary, is hard to achieve and maintain. Many gauges have a "lug" on the back. That is supposed to touch cluster metal. Cluster touches dash metal and so on..........back to the battery. A torturous path relying somewhat on just intimate contact, maybe a few sheet metal fasteners.
NOTE 2: The sending unit needs to be grounded by attaching a wire to one of it's flange screws and then to bare metal spot on frame.
NOTE 3. Always nice to know make model year of vehicle.
NOTE 4. Be careful making statements like "grounds are good". The approach for trouble shooting is to be pessimistic, not optimistic, because something is wrong and you don't know what. So everything is on the "person of interest" list.
Note to all future tank and gauge replacers:
You must assemble the components on the bench and test them together BEFORE installing. This area comes up many times as Martin said. You MUST establish a base line/boiler plate system on the bench and move the float arm up and down to observe If it works, how accurate it is, if it needs needle tweak, better grounds, compatibility, bad new parts, etc. Some folks will "calibrate" the set on the bench for accuracy. The gauge and the sender are some of the most difficult components to reach and test after they are installed. Knowing they work is a good advantage later on and saves your back, your knees, your neck and your butt.
