Installed my new fuel tank today all went well until after I filled my fuel tank and drove around for awhile than my gas gauge went to the 3 o'clock position. Read some threads rechecked my grounds than checked the connections at the fuel sender harness looked ok. checked the sending unit wire with a little tug and the wire just pulled out from on top of the tank. I remember thinking that the small cap on the sending wire seemed like it shound fit thighter. I should have closed it up a little or placed a strip of duct tape to hold it in place. I now am going to do some driving to burn some gas in order to drop the fuel level in tank again lower the tank and reinstalled the sending wire again. Is there a better way to hold the sending wire in place?

Solder.

not so sure solder is a good idea, I think there is an insulator under the brass stub and it seems it might melt. any other ideas

Herad solder would work, but I dont know.
hmm, I had no quams with mine. Might try 'pinching' the end that snaps to the stub?

I would crimp the connector slightly until it locks on securely.

It shouldn't come off after that.

I will crimp the connector tighter and duct tape. Don't want to pull that tank again.

Ditto on the crimping.