Temperature sending unit problem.

Then had an issue that the sender did not fix.
Could it be that I just got the wrong sender? Slantsixdan suggest this https://www.amazon.com/dp/B000C81UZY/?tag=2402507-20. The new one I put in was a duralast TU22. It came with no red tape on it. The picture is exactly the way it looks. The one slantsixdan suggested has no tape covering on it either. I have been told that if it doesn’t have any tape on it it will not function properly. The gauge obviously works to a certain extent otherwise it wouldn’t move at all when I grounded it. I don’t have a mopar c-3826 tester to test the gauges. I really do not want to pull out the dash to test this because I’m afraid I’ll never get it back together right. I’m really kind of clueless at this point. I have a connection when I test the battery ground and the sending wire so I’ve ruled out bad wire.